Common Amino Acids Research Articles

Bis(Tryptophan) Amphiphiles Form Ion Conducting Pores and Enhance Antimicrobial Activity against Resistant Bacteria.

The compounds referred to as bis(tryptophan)s (BTs) have shown activity as antimicrobials. The hypothesis that the activity of these novel amphiphiles results from insertion in bilayer membranes and transport of cations is supported by planar bilayer voltage-clamp studies reported herein. In addition, fluorescence studies of propidium iodide penetration of vital bacteria confirmed enhanced permeability. It was also found that BTs having either meta-phenylene or n-dodecylene linkers function as effective adjuvants to enhance the properties of FDA-approved antimicrobials against organisms such as S. aureus. In one example, a BT-mediated synergistic effect enhanced the potency of norfloxacin against S. aureus by 128-fold. In order to determine if related compounds in which tryptophan was replaced by other common amino acids (H2N-Aaa-linker-Aaa-NH2) we active, a family of analogs have been prepared, characterized, and tested as controls for both antimicrobial activity and as adjuvants for other antimicrobials against both Gram-negative and Gram-positive bacteria. The most active of the compounds surveyed remain the bis(tryptophan) derivatives.

U2af1 is a haplo-essential gene required for hematopoietic cancer cell survival in mice.

Somatic mutations in the spliceosome gene U2AF1 are common in patients with myelodysplastic syndromes. U2AF1 mutations that code for the most common amino acid substitutions are always heterozygous, and the retained WT allele is expressed, suggesting that mutant hematopoietic cells may require the residual WT allele to be viable. We show that hematopoiesis and RNA splicing in U2af1 heterozygous knockout mice were similar to those in control mice, but that deletion of the WT allele in U2AF1(S34F) heterozygous mutant-expressing hematopoietic cells (i.e., hemizygous mutant) was lethal. These results confirm that U2AF1 mutant hematopoietic cells are dependent on the expression of WT U2AF1 for survival in vivo and that U2AF1 is a haplo-essential cancer gene. Mutant U2AF1(S34F)-expressing cells were also more sensitive to reduced expression of WT U2AF1 than nonmutant cells. Furthermore, mice transplanted with leukemia cells expressing mutant U2AF1 had significantly reduced tumor burden and improved survival after the WT U2af1 allele was deleted compared with when it was not deleted. These results suggest that selectively targeting the WT U2AF1 allele in heterozygous mutant cells could induce cancer cell death and be a therapeutic strategy for patients harboring U2AF1 mutations.

Monomers of Glycine and Serine Have a Limited Ability to Hydrate in the Atmosphere.

The role of atmospheric aerosols on climate change is one of the biggest uncertainties in most global climate models. Organic aerosols have been identified as potential cloud condensation nuclei (CCN), and amino acids are organic molecules that could serve as CCN. Amino acids make up a significant portion of the total organic material in the atmosphere, and herein we present a systematic study of hydration for two of the most common atmospheric amino acids, glycine and serine. We compute DLPNO/CCSD(T)//M08-HX/MG3S thermodynamic properties and atmospheric concentrations of Gly(H2O)n and Ser(H2O)n, where n = 1-5. We predict that serine-water clusters have higher concentrations at n = 1 and 5, while glycine-water clusters have higher concentrations at n = 2-4. However, both glycine and serine are inferred to exist primarily in their nonhydrated monomer forms in the absence of other species such as sulfuric acid.

Molecular Epidemiology, Antifungal Susceptibility, and Virulence Evaluation of Candida Isolates Causing Invasive Infection in a Tertiary Care Teaching Hospital.

BackgroundThe incidence of invasive candidiasis is increasing worldwide. However, the epidemiology, antifungal susceptibility, and virulence of Candida spp. in most hospitals remain unclear. This study aimed to evaluate invasive candidiasis in a tertiary care hospital in Nanchang City, China.MethodsMALDI-TOF MS and 18S rDNA ITS sequencing were used to identify Candida strains. Randomly amplified polymorphic DNA analysis was used for molecular typing; biofilm production, caseinase, and hemolysin activities were used to evaluate virulence. The Sensititre™ YeastOne YO10 panel was used to examine antifungal susceptibility. Mutations in ERG11 and the hotspot regions of FKS1 of drug-resistant strains were sequenced to evaluate the possible mechanisms of antifungal resistance.ResultsWe obtained 110 Candida strains, which included 40 Candida albicans (36.36%), 37 C. parapsilosis (33.64%), 21 C. tropicalis (19.09%), 9 C. glabrata (8.18%), 2 C. rugose (1.82%), and 1 C. haemulonii (0.91%) isolates. At a limiting point of 0.80, C. albicans isolates could be grouped into five clusters, C. parapsilosis and C. tropicalis isolates into seven clusters, and C. glabrata isolates into only one cluster comprising six strains by RAPD typing. Antifungal susceptibility testing revealed that the isolates showed the greatest overall resistance against fluconazole (6.36%), followed by voriconazole (4.55%). All C. albicans and C. parapsilosis isolates exhibited 100% susceptibility to echinocandins (i.e., anidulafungin, caspofungin, and micafungin), whereas one C. glabrata strain was resistant to echinocandins. The most common amino acid substitutions noted in our study was 132aa (Y132H, Y132F) in the azole-resistant strains. No missense mutation was identified in the hotpot regions of FKS1. Comparison of the selected virulence factors detectable in a laboratory environment, such as biofilm, caseinase, and hemolysin production, revealed that most Candida isolates were caseinase and hemolysin producers with a strong activity (Pz < 0.69). Furthermore, C. parapsilosis had greater total biofilm biomass (average Abs620 = 0.712) than C. albicans (average Abs620 = 0.214, p < 0.01) or C. tropicalis (average Abs620 = 0.450, p < 0.05), although all C. glabrata strains were either low- or no-biofilm producers. The virulence level of the isolates from different specimen sources or clusters showed no obvious correlation. Interesting, 75% of the C. albicans from cluster F demonstrated azole resistance, whereas two azole-resistant C. tropicalis strains belonged to the cluster Y.ConclusionThis study provides vital information regarding the epidemiology, pathogenicity, and antifungal susceptibility of Candida spp. in patients admitted to Nanchang City Hospital.

Molecular Characteristics, Antimicrobial Resistance, and Biofilm Formation of Pseudomonas aeruginosa Isolated from Patients with Aural Infections in Shanghai, China.

PurposeTo investigate molecular characteristics, antimicrobial resistance, and biofilm formation ability of Pseudomonas aeruginosa strains isolated from patients with aural infections.MethodsIsolates (n = 199) were collected from ear discharges of patients with aural infections from January 2019 to December 2020. Antimicrobial susceptibility testing was performed according to the Clinical and Laboratory Standards Institute guidelines. All isolates were subjected to multilocus sequence typing (MLST) with amplification and sequencing of seven housekeeping genes. Biofilm formation and eradication were quantitatively assessed in microtiter plates. Genes associated with biofilm formation and the quinolone-resistance-determining region (QRDR) of genes gyrA and parC were investigated using polymerase chain reaction amplification and sequencing.ResultsOf the 199 P. aeruginosa strains isolated, 109 (54.77%) were from females and 90 (45.23%) were from males. The isolates exhibited very low rates of resistance to most antibiotics tested, including piperacillin (1.51%), ceftazidime (0.50%), and imipenem (3.52%); however, the quinolones ciprofloxacin (80.40%) and levofloxacin (82.91%) were notable exceptions. The QRDR sequence results of the quinolone-resistant P. aeruginosa isolates showed Thr83Ile (n = 155) was the most common amino acid mutation in gyrA (n = 165), while Ser87Leu (n = 157) was widely detected in parC (n = 165). MLST analysis identified 34 sequence types (STs) with most isolates belonging to ST316 (73.87%). Almost all of the P. aeruginosa isolates (96.98%) produced biofilms and biofilm-forming genes algD (98.49%), pslD (96.98%), and pelF (96.48%) were highly prevalent.ConclusionThe P. aeruginosa strains isolated from aural discharges in this study exhibited very low rates of resistance to most antibiotics tested, except for the resistance rates to quinolones, which were relatively high. The isolates also exhibited a strong biofilm formation ability and low susceptibility to eradication, indicating that more effective drugs and treatment methods are needed to combat these infections.

Evolution of the primate glutamate taste sensor from a nucleotide sensor

Taste perception plays an essential role in food selection. Umami (savory) tastes are sensed by a taste receptor complex, T1R1/T1R3, that detects proteinogenic amino acids.1 High sensitivity to l-glutamate (l-Glu) is a characteristic of human T1R1/T1R3, but the T1R1/T1R3 of other vertebrates does not consistently show this l-Glu response.1,2 Here, we demonstrate that the l-Glu sensitivity of T1R1/T1R3 is a derived state that has evolved repeatedly in large primates that rely on leaves as protein sources, after their divergence from insectivorous ancestors. Receptor expression experiments show that common amino acid substitutions at ligand binding sites that render T1R1/T1R3 sensitive to l-Glu occur independently at least three times in primate evolution. Meanwhile T1R1/T1R3 senses 5'-ribonucleotides as opposed to l-Glu in several mammalian species, including insectivorous primates. Our chemical analysis reveal that l-Glu is one of the major free amino acids in primate diets and that insects, but not leaves, contain large amounts of free 5'-ribonucleotides. Altering the ligand-binding preference of T1R1/T1R3 from 5'-ribonucleotides to l-Glu might promote leaf consumption, overcoming bitter and aversive tastes. Altogether, our results provide insight into the foraging ecology of a diverse mammalian radiation and help reveal how evolution of sensory genes facilitates invasion of new ecological niches.

Genetic polymorphism of the extracellular region in surface associated interspersed 1.1 gene of Plasmodium falciparum field isolates from Thailand

BackgroundA novel variable surface antigens (VSAs), Surface-associated interspersed proteins (SUFRINs), is a protein that is modified on the surface of infected red blood cell (iRBC). Modified proteins on the iRBC surface cause severe malaria, which can lead to death throughout the life cycle of a malaria parasite. Previous study suggested that SURFIN1.1 is an immunogenic membrane-associated protein which was encoded by using the surf1.1 gene expressed during the trophozoite and schizont stages. This study aimed to identify the regions of SURFIN1.1 and investigate the genetic diversity of the extracellular region of the surf1.1 gene.MethodsA total of 32 blood samples from falciparum malaria cases that were diagnosed in Si Sa Ket Province, Thailand were collected. Plasmodium genomic DNA was extracted, and the extracellular region of surf1.1 gene was amplified using the polymerase chain reaction (PCR). A sequence analysis was then performed to obtain the number of haplotypes (H), the haplotype diversity (Hd), and the segregating sites (S), while the average number of nucleotide differences between two sequences (Pi); in addition, neutrality testing, Tajima’s D test, Fu and Li’s D* and F* statistics was also performed.ResultsFrom a total of 32 patient-isolated samples, 31 DNA sequences were obtained and analysed for surf1.1 gene extracellular region polymorphism. Researchers observed six distinct haplotypes in the current research area. Haplotype frequencies were 61.3%, 16.2%, and 12.9% for H1, H2, and H3, respectively. The remaining haplotype (H4-H6) frequency was 3.2% for each haplotype. Hd was 0.598 ± 0.089 with the Pi of 0.00381, and S was 15. The most common amino acid polymorphic site was E251Q; other sites included N48D, I49V, E228D, E235S, L265F, K267T, E276Q, and S288F. Fu and Li’s D* test value was − 1.24255, Fu and Li’s F* test value was − 1.10175, indicating a tendency toward negative balancing selection acting on the surf1.1 N-terminal region. The most polymorphic region was variable 2 (Var2) while cysteine-rich domain (CRD) was conserved in both the amino acid and nucleotide extracellular region of surf1.1 gene.ConclusionsThe Thai surf1.1 N-terminal region was well-conserved with only a few polymorphic sites remaining. In this study, the data regarding current bearing on the polymorphism of extracellular region of surf1.1 gene were reported, which might impact the biological roles of P. falciparum. In addition, may possibly serve as a suitable candidate for future development of SURFIN-based vaccines regarding malaria control.Graphic abstract

Colorimetric and Fluorescent Dual-Signal Chemosensor for Lysine and Arginine and Its Application to Detect Amines in Solid-Phase Peptide Synthesis.

Lysine (Lys) and arginine (Arg), as two of the most alkaline amino acids among 20 common amino acids, are closely involved in many vital biological processes and biomaterial synthesis. Abnormal levels of Lys and Arg can lead to various diseases. Although a limited number of fluorescent probes for Lys and Arg have been reported, many of them are not sensitive enough due to the moderate fluorescence signal and on-off mode. In addition, none of them were applied for detecting amine groups in solid-phase peptide synthesis. In this study, we designed and synthesized optical fluorescent probe 1 based on the benzoxadiazole fluorophore, which could undergo an accelerated hydrolysis reaction under basic conditions. Probe 1 revealed excellent selectivity toward alkaline Lys and Arg over other common amino acids with both fluorometric and colorimetric readouts. After treatment with Lys and Arg, probe 1 could emit a turn-on fluorescent response at 580 nm with a distinct color change from pink to yellow. The limit of detection for Lys and Arg was calculated to be 1.1 and 1.39 μM, respectively. We also successfully applied probe 1 for the visualization of Arg in living cells. Moreover, to the best of our knowledge, probe 1 provided the first fluorescent platform to detect -NH2 groups in solid-phase synthesis of peptides with distinct fluorescent and colorimetric changes. We envision that the probe can provide an alternative method for the traditional Kaiser test.

A thermodynamic model of protein structure evolution explains empirical amino acid substitution matrices.

Proteins evolve under a myriad of biophysical selection pressures that collectively control the patterns of amino acid substitutions. These evolutionary pressures are sufficiently consistent over time and across protein families to produce substitution patterns, summarized in global amino acid substitution matrices such as BLOSUM, JTT, WAG, and LG, which can be used to successfully detect homologs, infer phylogenies, and reconstruct ancestral sequences. Although the factors that govern the variation of amino acid substitution rates have received much attention, the influence of thermodynamic stability constraints remains unresolved. Here we develop a simple model to calculate amino acid substitution matrices from evolutionary dynamics controlled by a fitness function that reports on the thermodynamic effects of amino acid mutations in protein structures. This hybrid biophysical and evolutionary model accounts for nucleotide transition/transversion rate bias, multi‐nucleotide codon changes, the number of codons per amino acid, and thermodynamic protein stability. We find that our theoretical model accurately recapitulates the complex yet universal pattern observed in common global amino acid substitution matrices used in phylogenetics. These results suggest that selection for thermodynamically stable proteins, coupled with nucleotide mutation bias filtered by the structure of the genetic code, is the primary driver behind the global amino acid substitution patterns observed in proteins throughout the tree of life.

Nutraceutical Study on Maianthemum atropurpureum, a Wild Medicinal Food Plant in Northwest Yunnan, China.

Maianthemum atropurpureum (Franch) LaFrankie (Asparagaceae), called nibai in Tibetan or dongka in Drung or zhu-ye-cai in local Chinese, is a wild vegetable consumed by the Tibetan people and other ethnic groups in Northwest Yunnan, China. It is also a traditional medicinal plant used by different linguistic groups for antimicrobial purposes. However the nutritional and phytochemical compositions of this important medicinal food plant have not been well studied previously. In this study, the nutrient content for nibai was determined by the China National Standards (GB) methods, and the phytochemical analysis involved multiple chromatographic and spectral methods including LC-TOF-MS analysis. Dried nibai is a rich source of protein (ca. 24.6%), with 18 of the 21 common amino acids. The amino acid content of nibai can reach up to 17.9/100 g, with the essential amino acids as major contributors, corresponding to 42.3% of the total amino acids. Nibai contains rich mineral elements, dietary fiber, vitamins, β-carotene, carbohydrates, and lipids. The phytochemical content of nibai was examined by conventional isolation strategies, as well as HR-ESI-TOF-MS to detect and identify 16 compounds including nine steroid saponins and seven flavonoids. Among these compounds, uridine, adenosine, guanosine, and β-methyl-6-methyl-d-glucopyranoside were found from the genus Maianthemum for the first time. These results help to demonstrate that the local people’s practice of consuming Maianthemum atropurpureum is reasonable due to its high levels of vitamins, minerals, essential amino-acids, and phytochemicals. Nibai may be further developed in Tibet and surrounding regions, and beyond as a health food, nutraceutical, and/or dietary supplement product.

Relative abundance of saccharides, free amino acids, and other compounds in specific pollen species for source profiling of atmospheric aerosol

Though studies in bioaerosols are being conducted with increasing frequency over the past decade, the total breadth of knowledge on bioaerosols and their role in atmospheric processes is still minimal. In order to better characterize the chemical composition of fresh biological aerosol for purposes of source apportionment and tracing in the atmosphere, several plant pollen species were selected for detailed chemical analyses. For this purpose, different pollen species were purchased and collected around Reno, Nevada, USA, for further extraction and detailed chemical analysis. These species included aspen, corn, pecan, ragweed, eastern cottonwood, paper mulberry, rabbitbrush, bitterbrush, lodgepole pine, and Jeffrey pine. Saccharides, free amino acids, and various other polar compounds (e.g., anhydrosugars and resin acids) were quantitatively analyzed using gas chromatography and ultra-high performance liquid chromatography coupled with mass spectrometry techniques (GC–MS and UPLC-MS), with the purpose to identify differences and nuances in chemical composition of specific pollen species. The saccharides β-d-fructose, α-d-glucose, and β-d-glucose were ubiquitously found across all pollen samples (10), and sucrose was found in five samples. d-galactose was also found in pine species. Total saccharides were 4.0 to 29% of total dry weight across all samples. Total free amino acids were 0.29% to 15% of total dry weight across all samples, with the most common amino acid being proline. Chemical profiles (including both saccharides and amino acids) of surface-deposited aerosol in the Lake Tahoe area correlated most closely with pine pollen than other analyzed pollen species, indicating that chemical profiles of pollen can be used to infer its contribution to local aerosols.

Genome-Wide Identification and Characterization of Amino Acid Polyamine Organocation Transporter Family Genes Reveal Their Role in Fecundity Regulation in a Brown Planthopper Species (Nilaparvata lugens).

The brown planthopper (BPH), Nilaparvata lugens Stål (Hemiptera:Delphacidae), is one of the most destructive pests of rice worldwide. As a sap-feeding insect, the BPH is incapable of synthesizing several amino acids which are essential for normal growth and development. Therefore, the insects have to acquire these amino acids from dietary sources or their endosymbionts, in which amino acid transporters (AATs) play a crucial role by enabling the movement of amino acids into and out of insect cells. In this study, a common amino acid transporter gene family of amino acid/polyamine/organocation (APC) was identified in BPHs and analyzed. Based on a homology search and conserved functional domain recognition, 20 putative APC transporters were identified in the BPH genome. Molecular trait analysis showed that the verified BPH APC family members were highly variable in protein features, conserved motif distribution patterns, and exon/intron organization. Phylogenetic analysis of five hemipteran species revealed an evolutionary pattern of interfamily conservation and lineage-specific expansion of this gene family. Moreover, stage- and tissue-specific expression analysis revealed diverse expression patterns in the 20 BPH APC transporter genes. Lastly, a potential BPH fecundity regulatory gene of NlAPC09 was identified and shown to participate in the fecundity regulation through the use of quantitative polymerase chain reaction (qPCR) and RNA inference experiments. Our results provide a basis for further functional investigations of APC transporters in BPH.

Amino group-driven distinguishing homocysteine from cysteine and glutathione in photoluminesecent signal of the iridium(III) complexes

In this work, six iridium(III) complexes have been designed, synthesized and characterized. The molecular structures of complex 1 ([(pba)2Ir(bpy-2N(CH3)2)]PF6), 2 ([(pba)2Ir(bpy-2NH2)]PF6) and 3 ([(pba)2Ir(bpy-2CH3)]PF6) were determined by single crystal X-ray diffraction. Upon addition of Hcy (homocysteine) to the solution of complex 1, a luminescent variation from orange red to green was observed by the naked eye, corresponding to a large blue shift from 604 nm to 498 nm (~106 nm). While the emission intensity of complex 1 was almost no change after addition of other common amino acids including Cys (cysteine) and GSH (glutathione). The aldehyde group of complex 1 formed a new thiazinane/thiazolidine ring with Hcy/Cys confirmed by 1H NMR and high-resolution mass spectrometry. And the new product 1-Hcy had a higher quantum yield than 1-Cys. Theoretical calculations showed that the HOMO (highest occupied molecular orbital) of 1-Hcy was located on the newly formed six-membered thiazinane ring, which was different from the HOMO of 1-Cys. Compared with the other iridium(III) complexes, we can speculate that the large blue shift and enhancement of the emission intensity of the complex 1 were related to the strong electron donating ability of the modified amino groups on bipyridine ligand. This will provide an idea for the design of ratio-based luminescence probes for Hcy in future.

Molecular characteristics and phylogenetic analysis of novel goose parvovirus strains associated with short beak and dwarfism syndrome

Short beak and dwarfism syndrome (SBDS) emerged in Cherry Valley duck flocks in China in 2015, and novel goose parvovirus (NGPV) was shown to be the etiological agent of SBDS. To date, it is not known whether SBDS-related NGPV isolates possess common molecular characteristics. In this study, three new NGPV strains (namely, SDHT16, SDJN19, and SDLC19) were isolated from diseased ducks showing typical signs of SBDS and successfully passaged in embryonated goose or Cherry Valley duck eggs. The complete genome sequences of these NGPV strains were 98.9%-99.7% identical to each other but showed slightly less similarity (95.2%-96.1% identity) to classical GPV strains. A total of 16 common amino acid substitutions were present in the VP1 proteins of six NGPV strains (SDHT16, SDJN19, SDLC19, QH, JS1, and SDLC01) compared with the classical Chinese GPV strains, nine of which were identical to those found in European GPV strain B. The non-structural protein Rep1 of the six NGPV strains had 12 common amino acid substitutions compared with the classical GPV strains. Phylogenetic analysis indicated that the Chinese NGPV strains clustered with the European SBDS-related NGPV strains, forming a separate branch that was distinct from the group formed by the classical GPV strains. The present study shows the common molecular characteristics of NGPV isolates and suggests that the Chinese NGPV isolates probably share a common ancestor with European SBDS-related NGPV strains.

Antioxidative, cytotoxic, and anti-metastatic potentials of Laurencia obtusa and Ulva lactuca seaweeds

Objective: To investigate the antioxidant and cytotoxic properties of the most active extracts from Ulva lactuca and Laurencia obtusa against colon and cervical cancer cell lines. Methods: The antioxidant radical scavenging activity of the algal extracts was estimated using the 2,2-diphenyl-1-picrylhydrazyl colorimetric assay. Moreover, the cytotoxic potential of these bioactive extracts was studied against HCT-116 and HeLa cells by 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyltetrazolium bromide assay. Wound healing analysis was adopted to evaluate the anti-metastatic effects of protein extracts from both algae. Cell cycle analysis was performed by flow cytometry, and apoptotic bodies were detected using 4’,6-diamidino-2-phenylindole fluorescent staining. Amino acids of hydrolyzed protein extract were separated and identified chromatographically by high performance liquid chromatography. Results: The green algae Ulva lactuca had higher lipid content than Laurencia obtusa, whereas the latter had higher protein content with high antioxidant capacity. Protein extracts had significant dose- and time-dependent cytotoxicity and anti-metastatic activity against HCT-116 cells. Protein b extracts of both algae obtained from the chloroform:hexane solvent lipid-free residue caused morphological changes and induced apoptosis of HCT-116 cells. Further analysis revealed that apoptosis induced upon Laurencia obtusa protein b treatment was triggered via the ROS pathway, causing a significant increase in the sub-G1 population. Glycine and arginine (5.94 and 5.47 μM, respectively) were the most common amino acids in Laurencia obtusa protein b extract. Conclusions: Proteins of Laurencia obtusa and Ulva lactuca could be considered as an adjuvant nutraceutical source of pro-apoptotic and anti-metastatic biomolecules against colon cancer.

Genetic variability in VP1 gene of infectious bursal disease virus from the field outbreaks of Kerala, India.

Infectious bursal disease (IBD) is considered as menace as it affects poultry industry globally causing immunosuppression, high mortality and heavy economic loss. Outbreaks of IBD were reported in many states of India including Kerala. VP1 gene acts as an important factor in the process of virus encapsidation and its involvement in viral virulence and viral replication indicates its importance in infectious bursal disease virus (IBDV). The present study was conducted to carry out the molecular characterization of VP1 gene of virulent IBDV in Kerala. A total of 42 samples were processed for the detection and analysis of VP1 gene of IBDV. Out of 42 samples, 21 samples were positive for VP1 gene of IBD. The phylogenetic analysis of the partial VP1 gene sequences reveals the clustering of IBDV isolates into very virulent IBDV (vvIBDV) and non-virulent IBDV (vIBDV). Eighteen isolates (11 isolates from vaccinated flock and 7 from non-vaccinated flocks) clustered with very virulent strains. Three isolates (2 isolates were from vaccinated flock and 1 from non-vaccinated flock) clustered with non-virulent IBDV strains, showing more evolutionarily similarity to south Indian strain VCN14/ABT/MVC/India. It is observed that vvIBDV isolates from this study have common ancestor with the south Indian strain PY12 but showed 9-10% divergence from this strains. The amino acid analysis of these 21 isolates revealed that 17 isolates possessed the characteristic vvIBDV TDN amino acid triplet, while the three isolates had non-vIBDV NEG amino acid triplet at 145/146/147 position. The remaining isolate 1/CVASP/IBDV/VP1 shows unique PDN triplet instead of TDN. Two vvIBDV isolates (15/CVASP/IBDV/VP1 and 18/CVASP/IBDV/VP1) showed 100% nucleotide and amino acid similarity with intermediate plus vaccine strain. Four vvIBDV isolates showed neutral amino acid substitution K251R which was earlier reported in Indian strains but first time in south Indian isolates. The most common unique amino acid substitution observed in our study was neutral E269D amino acid substitution in 12 isolates, neutral amino acid substitution T329S in five isolates, neutral T174N and non-polar to polar amino acid substitution A178T in isolate 10/CVASP/IBDV/VP1, non-polar to polar amino acid substitution P360R in isolate 17/CVASP/IBDV/VP1 and non-polar to polar amino acid substitution P188S in isolate 1/CVASP/IBDV/VP1. These novel mutations in our study reveal the role of genetic drift in the evolution of vvIBDV strains. The isolate 2/CVASP/IBDV/VP1 from non-vaccinated flock shows VP1 gene of non-vIBDV, but possessing VP2 of vvIBDV type indicates this is evolved by genetic shift of segments A and B. This is the first genetic characterization study of field VP1 gene of IBDV isolates in Kerala, India.

Analysis and evaluation of nutritional components of &amp;lt;italic&amp;gt;Collichthys lucidus&amp;lt;/italic&amp;gt; muscles from Mindong waters

<italic>Collichthys lucidus</italic> is an important small economic fish species in coastal areas of China. Because of fast growth, large catches and delicious taste, it is loved by people of Fujian and Zhejiang in China. At present, there are only a few studies of <italic>C</italic>. <italic>lucidus</italic> on nutrition. To improve the basic data of quality and nutritional composition of muscle in this species, this study analyzed and evaluated the nutrient composition of <italic>C</italic>. <italic>lucidus</italic> muscles from Mindong waters. Nutritional components in muscle of <italic>C</italic>. <italic>lucidus</italic> were tested and analyzed with routine methods. Samples of 30 wild individuals, with (12.45±1.25) cm in body length and (37.15±13.25) g in body weight, were collected from Mindong waters during the reproductive season. The results showed that contents of moisture, crude ash, crude protein and crude fat of fresh muscles were (77.70±0.21)%, (1.49±0.59)%, (17.21±0.27)% and (0.56±0.05)%, respectively. There were 17 common amino acids found in muscles, including 7 essential amino acids (except Trp). In fresh sample, the total content of amino acids was (17.01±0.11)%, the content of essential amino acids was (6.09±0.06)%; in dry sample, the total content of amino acids was (76.30± 0.44)%; the content of essential amino acids was (27.33±0.29)%; the percentage of essential amino acids in total amino acids was 35.82%; the ratio of amino acids to no-essential amino acids (EAA/ NEAA) was 66.73%. The constitutional rate of the essential amino acids accorded with the FAO/WHO standard fundamentally. According to nutrition evaluation in amino acids score (AAS) and chemical score (CS), the first limited amino acid was Val, and the second limited amino acids were Leu and Phe+Tyr; the essential amino acids index (EAAI) was 67.04. In dry sample, the content of four kinds delicious amino acids was (26.24±0.01)%, and the percentage of delicious amino acids in total amino acids was 34.40%. 27 fatty acids were found in muscle of <italic>C</italic>. <italic>lucidus</italic>. There were 12 types of saturated fatty acids, accounting for (56.48±0.10)% of the total fatty acids. The content of C18∶0 in saturated fatty acids was the highest, accounting for (32.77±0.42)% of the total fatty acids. There were 7 types of monounsaturated fatty acids, accounting for (13.22±0.12)% of the total fatty acids, and 8 types of polyunsaturated fatty acids, accounting for (30.31±0.18)% of the total fatty acids. The percentages of EPA and DHA in total fatty acids of <italic>C</italic>. <italic>lucidus</italic> were (8.23±0.14)% and (13.22±0.12)%, respectively. The composition of trace elements in muscles of <italic>C</italic>. <italic>lucidus</italic> was reasonable. Therefore, <italic>C</italic>. <italic>lucidus</italic> is delicious fish species with balanced nutrition and relatively high nutritional value, which deserves further exploitation and popularization.

Genetic characterization and phylogenetic analysis of porcine epidemic diarrhea virus in Guangdong, China, between 2018 and 2019.

Porcine epidemic diarrhea virus (PEDV), a leading cause of piglet diarrhea outbreaks, poses a significant danger to the swine industry. The aim of this study was to investigate the epidemic characteristics of PEDV that was circulating in Guangdong province, one of China’s major pig producing provinces. Clinical samples were collected from eight pig farms in Guangdong province between 2018 and 2019 and tested for the major porcine enteric pathogens, including PEDV, transmissible gastroenteritis virus (TGEV), Swine enteric coronavirus (SeCoV), Swine acute diarrhea syndrome coronavirus (SADS-CoV), porcine deltacoronavirus (PDCoV), and porcine rotavirus (RV). As a result, only PEDV and RV were detected at a rate of 47.0% (16/34) and 18.6% (8/34), respectively. Coinfectoin with PEDV and RV occurred at a rate of PEDV 12.5% (2/16). Subsequently, the full-length S gene sequences of 13 PEDV strains were obtained, and phylogenetic analysis suggested the presence of GII-c group PEDV strains in this region (non-S-INDEL). Two novel common amino acid insertions (55T/IG56 and 551L) and one novel glycosylation site (1199G+) were detected when the CV777 and ZJ08 vaccine strains were compared. Furthermore, intragroup recombination events in the S gene regions 51–548 and 2478–4208 were observed in the PEDV strains studied. In summary, the observations provide current information on the incidence of viral agents causing swine diarrhea in southern China and detailed the genetic characteristics and evolutionary history of the dominant PEDV field strains. Our findings will aid in the development of an updated vaccine for the prevention and control of PEDV variant strains.

A Distinctive Pattern of Diversity for the TAS2R38 Gene in North Africa.

The TAS2R38 gene is involved in bitter taste perception. This study documents the distinctive diversity patterns in northern Africa of functional single-nucleotide polymorphisms (SNPs) rs713598 and rs1726866 at the TAS2R38 locus and places those patterns in the context of global TAS2R38 diversity. Data previously genotyped with TaqMan assay were analyzed for rs713598 and rs1726866 for 375 unrelated subjects (305 Tunisians from seven locations: Mahdia, Sousse, Kesra, Nebeur, Kairouan, Smar, and Kerkennah; plus 70 Libyans). Data were analyzed to present haplotypes and genotypes before comparison with data from worldwide populations. This study provides information about TAS2R38 diversity in a part of the world that is relatively understudied. Considering the two SNPs rs713598 and rs1726866, the CA nucleotide haplotype leading to the PV amino acid haplotype is extremely rare almost everywhere, but it is relatively frequent (between 6% and 15%) in northern Africa, where it coexists with the globally common amino acid haplotypes PA, AA, and AV. Given its higher frequency in North Africa, the authors propose the CA nucleotide haplotype as a biogeographic marker for forensic purposes.

Rapid Point of Care Diagnostic Test for the Detection of Rare Metabolic Disorders

Rapid Point of Care Diagnostic Test for the Detection of Rare Metabolic Disorders