Partial Sequence Analysis Research Articles

Bargibant’s pygmy seahorse Hippocampus bargibanti in Taiwan Bank: hidden biodiversity of Taiwan Strait

During a scientific expedition in the Taiwan Bank in the southern Taiwan Strait in 2021, five pygmy seahorses, measuring between 18.1 mm and 28.3 mm in standard length, were inadvertently collected along with Muricella sea fans. Morphometric measurements of these pygmy seahorse specimens coincided with the previous data on H. bargibanti, but they had a proportionally greater head depth and snout length. Genetically, DNA marker analysis of partial mitochondrial COI sequences confirmed that our specimens belonged to the same lineage as H. bargibanti, with a p-distance of 0.54% among populations. This discovery enhances our knowledge of the limited biodiversity in the Taiwan Bank, which includes a complex geomorphology of both reef banks and sandy substrates, and highlights the importance of strict laws prohibiting fishing with inadequate gear, invasive or illegal fishing, and sand dredging to protect unexplored coral reef biodiversity in the area.

The Molecular Detection and Therapeutic Management of Pathogenic Theileria luwenshuni Infection in a Goat: A Case Report

A 2-year-old female Assam Hill goat was presented with a clinical history of anorexia, fever, mild anemia, rough body coat, dehydration, tachycardia, dyspnea and swelling of palpable lymph nodes. Hematology revealed low hemoglobin, packed cell volume, red blood cell and thrombocyte count. Biochemical analysis showed increased serum concentration of alanine aminotransferase (ALT), aspartate aminotransferase (AST), creatinine and urea in comparison to the normal reference range. Microscopic examination showed intra-erythrocytic forms of Theileria species. Molecular and phylogenetic analysis of partial 18S rRNA gene sequence confirmed Theileria luwenshuni infection. The goat was treated with buparvaquone and oxytetracycline and recovered uneventfully. A three-month follow-up showed no recurrence. This study reveals the presence of T. luwenshuni in Assam, India and it should be considered in differential diagnosis and as one of the important pathogens of clinically sick goats. The present case report provides a rational approach to diagnosis and treatment for a goat infected with pathogenic T. luwenshuni in Assam, India. To our knowledge, the present communication describes about the first successful therapeutic management of pathogenic Tluwenshuni infection in a goat supported with molecular evidence from Assam, a north-eastern state of India.

A new record of avian reovirus genogroup clusters isolated and molecularly characterized in chickens in Egypt

BackgroundThe global poultry industry has been experiencing increasing condemnation at slaughterhouses since 2011, due to the emergence of avian reovirus (ARV) variant strains. Recently seven ARV genogroup clusters were identified based on the σC sequence of the S1 segment that was used as a genetic marker to characterize and classify ARV.ResultsAmong ninety-seven suspected broilers, breeders, and commercial grandparent’s homogenates, ARV was PCR confirmed in thirty-five (36%). Samples were collected from different governorates in Egypt, including Giza–Ismailia–Sharqia–Menoufia, and Behira, between 2020 and 2023. A viral isolation trial was performed on weak positive samples, successfully isolating sixteen samples on the LMH cell line forming the characteristic giant cells of ARV infection. Partial sequencing and phylogenetic analysis of the σC gene of ten ARV PCR positive samples revealed the circulation of ARV genogroup clusters 1, 2, 4, and 5, eight samples being distinguished from commercially available vaccine strains with a low percentage of nucleotides and amino acid identities.ConclusionsThis research demonstrated that the ARV isolates were distinct compared to commercially available vaccine strains based on partial σC sequence. Detection, isolation, and classification of ARV as genogroups 1, 2, 4, and 5 are recorded. A vigilant surveillance to evaluate the ARV situation in Egypt is urgent. We recommend re-evaluating the ARV commercial vaccines by challenging them with circulating Egyptian field isolates, as well as their cross-protection. In addition, the development of autologous vaccines from both classical and variant strains to provide optimal protection.

Occurrence of atypical Pseudomonas viridiflava strains on different host plants in southern Italy

AbstractSince 1997, severe bacterial disease symptoms were observed during surveys carried out in farms with field‐grown Molfettese Catalogna chicory (Cichorium intybus var. sylvestre, Catalogna group), sugarloaf chicory (C. intybus var. porphyreum), curly type lettuce (Lactuca sativa var. crispa) cvs Langero and Aleppo, and safflower (Carthamus tinctorius) located in the Apulia and Basilicata regions of southern Italy. Convex colonies with yellowish mucoid material on hypersucrose medium (5% sucrose nutrient agar), producing fluorescent pigments on King's medium B, were isolated from all symptomatic plants. Based on conventional biochemical and nutritional tests, Biolog assays, and analysis of partial 16S rDNA and rpoB sequences, these atypical fluorescent Pseudomonas isolates were identified as Pseudomonas viridiflava. The pathogenicity of the isolates was ascertained by artificial inoculation on their respective original hosts. The analysis of rpoB gene sequences and RAPD‐PCR profiles showed a high genetic variability among the P. viridiflava isolates. To the best of our knowledge, this is the first report of bacterial diseases on horticultural crops caused by atypical strains of P. viridiflava in Italy and the first report of the bacterium on safflower. In addition, P. viridiflava is reported for the first time as a causal agent of leaf spot on potato (Solanum tuberosum). The economic importance of chicory and curly type lettuce in southern Italy and recent spread of atypical and highly virulent P. viridiflava strains require more extensive and careful phytosanitary surveillance, as well as an adjustment of sustainable crop protection management to cope with this new challenge.

Surveillance of coronavirus in wild mammals seized and rescued by the National Forest and Wildlife Service of Peru

Coronaviruses are common around the world and infect a wide variety of animals, including domestic and wild ones. They are characterized by causing respiratory, enteric, hepatic, and neurological diseases of varying severity, from asymptomatic to severe. Wild animals play a crucial role in this group of viruses since they can act as hosts or reservoirs for pathogenic species of humans and domestic animals. The purpose of this study was to molecularly identify coronaviruses present in wild mammals seized and rescued by the National Forestry and Wildlife Service (SERFOR) of Peru. We molecularly analyzed tracheal and rectal swabs from 90 wild mammals seized and/or rescued by SERFOR, partially amplifying the coronavirus RdRp gene. Ten of the 90 animals studied (11.1%) were positive only for Alphacoronavirus. These were non-human primates (Aotus sp., Sapajus apella, and Saimiri sciureus), the crab-eating raccoon (Procyon cancrivorus), and the South American sea lion (Otaria flavescens). The partial sequence analysis of the RdRp gene revealed that nine sequences belonged to the Pedacovirus subgenus and shared 99.1% nucleotide identity with the porcine epidemic diarrhea virus (PEDV), and only one sequence belonged to the Tegacovirus subgenus and shared 95.6% identity with the Feline coronavirus (FCoV). The results show that various wild mammal species from Peru can act as hosts for coronaviruses capable of infecting domestic species. Due to this, it is necessary to implement measures that help us identify the genera and species of coronaviruses in these species to prevent and contain future epidemics or pandemics resulting from the high rate of recombination and mutation of this virus.

First detection of D181 genotype of infectious bronchitis in poultry flocks of Morocco

BackgroundThis paper reports the first pathological and molecular characterization of the novel variant of infectious bronchitis virus (IBV) D181 in poultry flocks in Morocco and Africa.MethodsThe study includes six poultry farms, involving three flocks of layers aged between 28 and 67 weeks and three broiler flocks aged 27, 39 and 42 days from different regions of Morocco. In all affected layer flocks, a severe drop in egg production with poor eggshell quality was reported. Necropsy of dead birds was carried out, and samples of trachea, lungs, oviduct, ovaries, and kidneys were fixed in 10% neutral buffered formalin for histopathologic examinations, while other portions were stored at -20 °C for molecular analysis. Real time RT-qPCR for IBV gene group was performed, and IBV variants were identified. Partial S1 gene sequences were amplified by conventional RT-PCR, sequenced, and aligned for phylogenetic and amino acid similarity analysis.ResultsNecropsy of dead birds revealed misshapen and hemorrhagic ovarian follicles with an edematous oviduct and severe reaction in the cecal tonsils. A caseous material accumulation in the sinus was noted in few birds. In contrast, the broiler flocks exhibited respiratory clinical signs such as difficulty in breathing, sneezing, tracheal rales, watery eyes and lethargy, associated with a decrease in feed consumption. Mortality in broiler ranged from 2 to 15%. Histopathological analysis of samples showed a lympho-plasmocytic inflammation in the oviduct, trachea, and lungs. Individual necrosis of epithelial cells, with sloughing of the bronchial epithelium and accumulation of desquamated cells with mucus in the airways, was observed in some birds. Partial S1 gene sequencing and phylogenetic analyses showed that the Moroccan strains were very closely related to D181 strains isolated in Dutch layers and breeders in 2018. Nucleotide sequence identities reached 90.9–95% with the Dutch isolates (strain CK/NL/D181/2018).ConclusionOur sequencing results demonstrate for the first time that the D181 IBV genotype is circulating in Moroccan poultry. These findings justify permanent monitoring of circulating strains in order to appropriately adjust vaccination strategies to align with the evolving field situation.

First Modern Morphological and Molecular Description of Saccocoelium Cephali Larvae Stages (Digenea: Haploporidae) from the Black Sea.

Knowledge of haploporid trematode larvae is very poor. Until recently, only scattered reports from the Black and Medditeranean Seas were known. The present research is the first report of haploporid cercariae S. cephali from the gastropod Hydrobia acuta inhabiting the Black Sea. Thus, the present study aimed to investigate the larvae of one species from the Haploporidae family. Hydrobia acuta molluscs were collected in the estuary of the Chernaya River (the Black Sea) during 2011-2013 and examined for trematode larvae. Found parthenitae were drawn and preserved for DNA extractions. Morphological features were compared to nominal species, and molecular comparisons were made of the subunit ribosomal DNA with other Haploporidae species. The haploporid parthenitae were found in the gonads of Hydrobia acuta molluscs. Most of the morphological characteristics of the specimens investigated agree with those of Saccococoelium sp. and are closest to those of S. cephali by shape and length of the body, ratio of suckers, ratio of tail length to body, shape, and size of the pharynx. Phylogenetic analysis from our study generated with Bayesian algorithm showed that studied cercariae specimens from the Black Sea were within the hapolporine clade and closely related to S. cephali from Spain. Morphological characteristics of cercariae emerging from Hydrobia acuta from the Black Sea and the analysis of partial 28S rDNA sequences support the conspecificity of the parasite with S. cephali mature worms from the Mediterranean Sea.

First report on genetic characterization of egg drop syndrome 1976 virus in Egypt.

Since its first description in 1991 in Egypt, egg drop syndrome 1976 (EDS-76) virus has received a little attention as a potential cause for the drop in egg production as well as the reduction in egg quality. To date, no studies have been carried out to describe the genetic characteristics of the circulating field EDS-76 virus strains. Thus, the present study was attempted to estimate the emergence of EDS-76 virus in layer flocks and to determine the genetic diversity between the field strains and the vaccine strain 127. During 2022, a total of 5 apparently healthy backyard layer flocks were investigated for the presence of EDS-76 virus infection following complaints of sudden drop in egg production (25-30%), accompanied by high incidence of eggshell defects. EDS-76 virus DNA was detected in the oviduct samples of 4 (80%) flocks by polymerase chain reaction (PCR) assay targeting the hexon gene of the viral capsid. Attempts of viral isolation in duck embryo revealed no embryonic mortality, however, the allantoic fluids of inoculated eggs exhibited a sustained increase in the hemagglutinating (HA) activity throughout three consecutive passages. The obtained strain, designated BH-1, was characterized on the basis of partial hexon gene sequence analysis (GenBank accession number OR531368). The BH-1 strain displayed 99.6% nucleotide identity with the vaccine strain 127. However, amino acid alignments with the vaccine strain 127 revealed that the BH-1 strain carried 5 non-synonymous mutations. In addition, two of these mutations were incorporated into the hexon hypervariable regions (HVRs), which are strictly responsible for eliciting serotype-specific neutralizing antibodies. In conclusion, the present study represents a starting point for genetic characterization of EDS-76 virus in Egypt and highlights the importance for continuous monitoring and characterization of the circulating field EDS-76 virus strains, in order to determine the proper control strategy.

Outbreak of Western Equine Encephalitis Virus Infection Associated with Neurological Disease in Horses Following a Nearly 40-Year Intermission Period in Argentina.

Western equine encephalitis virus (WEEV) is a mosquito-borne arbovirus (genus Alphavirus, family Togaviridae) that has re-emerged in South America in late 2023, causing severe disease in both horses and humans after a nearly 40-year intermission period. We here describe the virological, serological, pathological, and molecular features of WEEV infection in horses during the 2023-2024 outbreak in Argentina. WEEV-infected horses developed neurological signs with mild to severe encephalitis associated with minimal to abundant WEEV-infected cells, as demonstrated by WEEV-specific in situ hybridization. The distribution of viral RNA was multifocal, with predominance within neuronal bodies, neuronal processes, and glial cells in the medulla oblongata and thalamic regions. Phylogenetic analysis of partial nsP4 sequences from three viral isolates obtained from three different provinces of Argentina support grouping with other temporally current WEEV strains from Uruguay and Brazil under a recently proposed novel lineage.

1-Acetyl-β-Carboline from a Jeju Gotjawal Strain Lentzea sp. JNUCC 0626 and Its Melanogenic Stimulating Activity in B16F10 Melanoma Cells.

The genus Lentzea is a prolific source of bioactive and structurally diverse secondary metabolites. We isolated a novel strain, Lentzea sp. JNUCC 0626, from Hwasun Gotjawal on Jeju Island, Korea. Based on 16S rRNA partial gene sequence analysis, strain JNUCC 0626 is closely related to Lentzea isolaginshaensis NX62 (99.41% similarity), Lentzea pudingi DHS C021 (99.31%), and Lentzea cavernae SYSU K10001 (99.26%). From the fermentation broth of JNUCC 0626, we isolated 1-acetyl-β-carboline, whose structure was established using IR, HR-ESI-MS, and 1D- and 2D-NMR techniques. 1-acetyl-β-carboline was found to activate melanogenesis in mouse B16F10 cells without cytotoxicity at concentrations up to 50 μM. At this concentration, the compound increased melanin content by 27.44% and tyrosinase activity by 240.64% compared to the control, by upregulating key melanogenic enzymes, including tyrosinase, TRP-1, TRP-2, and microphthalmia-associated transcription factor (MITF), a central regulator of melanogenesis. In addition, 1-acetyl-β-carboline significantly inhibited ERK phosphorylation, reducing it by 20.79% at a concentration of 12.5 μM and by 25.63% at 25 μM. This inhibition supports the hypothesis that 1-acetyl-β-carboline enhances melanin synthesis by upregulating MITF and melanogenic enzymes via the ERK signaling pathway. This study aimed to isolate and identify 1-acetyl-β-carboline from a novel strain of Lentzea sp. JNUCC 0626, discovered in Gotjawal, Jeju Island, and to evaluate its effect on melanin production in B16F10 melanoma cells. Skin irritation tests on 32 subjects confirmed its safety for topical use, and the findings suggest that 1-acetyl-β-carboline, which enhances melanogenesis without cytotoxicity, holds promise as a therapeutic agent for hypopigmentation-related conditions or as a cosmetic ingredient.

Identification and fungicide screening of Phyllosticta capitalensis causing leaf spot on sweet viburnum in China

Sweet viburnum (Viburnum odoratissimum Ker-Gawl.) is a widely used ornamental plant, which has dense branches and leaves, and fast spreading and evergreen habit. In October 2022, leaf spot symptoms were observed in a hedge of sweet viburnum in Yuanshi Garden, Ningbo, China. Fungi were isolated from symptomatic leaves, and were identified using morphological characteristics and phylogenetic analyses of partial sequences of internal transcribed spacer (ITS), actin (act), and translation elongation factor 1-alpha (tef1-α), and were evaluated in pathogenicity tests. The causal agent of sweet viburnum leaf spot was identified to be Phyllosticta capitalensis. Effects of seven fungicides on P. capitalensis were assessed in vitro. Fungicide EC50s (mg L-1) against P. capitalensis were: 270.77 for 75% chlorothalonil (WP); 0.02 for 250 g L-1 azoxystrobin SC; 0.27 for 10% difenconazole WDG; 0.02 for 75% trifloxystrobin + tebuconazole WDG, 9.03 for 35% fluopyram + tebuconazole SC, 5.90 for 500 g L-1 fluazinam SC, and 89.11 for 10% prothioconazole SC. Among these, azoxystrobin SC and trifloxystrobin + tebuconazole WDG could be used for control of viburnum leaf spot. This is the first report of P. capitalensis causing leaf spot of sweet viburnum, and this study provides guidance for chemical management sweet viburnum leaf spot, and on other host plants.

Reassessment and phylogenetic position of the overlooked limacoid land snail Trochomorpha sculpticarina Martens, 1883 (Eupulmonata, Ariophantidae), with the description of a new genus

The Malay Peninsula has traditionally been considered to harbour a diverse land-snail fauna, both in terms of a high species richness and a wide variety of conchological traits, especially within the limacoid land snails. A recent survey along the Malay Peninsula of southern Thailand discovered an overlooked limacoid taxon “Trochomorpha” sculpticarina Martens, 1883, previously assigned to genus Trochomorpha of the Trochomorphidae. This genus is herein described as Janbinmorphagen. nov. based on comparative studies of shell morphology, external features, genital anatomy and radular morphology, as well as analyses of partial sequences of two mitochondrial markers, COI and 16S rRNA, and of one nuclear marker, 28S rRNA. This new genus is characterised by a combination of distinct morphological and anatomical features. The most distinguishing features are a depressed trochiform shell with a keeled last whorl, gametolytic organ without a duct, gametolytic sac with two lobes, and proximal epiphallus encircled with a thick sheath and attached by the penial retractor muscle. In addition, an analysis of the differentiation in mitochondrial and nuclear markers confirmed that this new genus, first recognised by morphology, is also genetically distinct. The molecular data also confirm that J. sculpticarinacomb. nov. is a member of the Ariophantidae and has a close evolutionary relationship to Hemiplecta and Maelamaodiscus.

Transmission patterns of malignant catarrhal fever in sheep and cattle in Karnataka, India.

Malignant catarrhal fever (MCF) presents a sporadic yet significant threat to livestock and wildlife. A comprehensive investigation in Karnataka, India into the prevalence and transmission patterns of sheep-associated MCF (SA-MCF) was conducted. A total of 507 sheep peripheral blood leukocyte samples from 13 districts along with 27 cows and 10 buffalo samples from various regions in Karnataka were tested for SA-MCF infection i.e. Ovine gammaherpesvirus 2 (OvHV-2) using heminested PCR. Furthermore, serum samples collected from 73 cows and 15 buffalo suspected of MCF were tested using a commercially available ELISA kit. Additionally, histopathological examinations of affected tissues and phylogenetic analysis of viral tegument protein sequences were conducted. Our findings indicated a 20.11%, 33.33% and 20% positivity for OvHV-2 in sheep, cows and buffalo respectively by PCR. Statistical analysis revealed a significant association between the age of sheep and the detection of OvHV-2. Seven cows and one buffalo serum samples tested positive for ELISA. Clinical findings in bovids were consistent with typical MCF signs, and histopathological results revealed multi-organ involvement characterised by necrotising vasculitis and lymphoid hyperplasia. The nucleotide pairwise identity matrix revealed 99.5% identity between the sequences obtained in the study with sequences from other states. The phylogenetic analysis of partial tegument protein sequences from bovid and sheep samples suggested a close genetic relationship between the local OvHV-2 strains and those from various global regions. Crucially, this study underscores the widespread presence of SA-MCF in Karnataka, with significant implications for both livestock management and wildlife conservation.

Sequence and phylogenetic analysis of FMD virus isolated from two outbreaks in Egypt

Despite intensive control efforts, Foot and mouth disease (FMD) outbreaks continue to occur regularly in Egypt and resulting in dramatic economic losses to the livestock industry. During 2018 and 2022, FMD was clinically suspected among previously vaccinated cattle in Beheira and Kafr El-Sheikh provinces, Egypt. FMDV RNA was detected in 18 (45%) out of 40 epithelial tissue samples using real-time RT-PCR based on a pan-FMDV primers set. The 2018 outbreak isolates (n = 8) included the FMDV serotypes A and SAT2, whereas all isolates (n = 10) from the 2022 outbreak belonged to the FMDV serotype A. Four selected isolates, designated FMDV/SAT2/EGY/Beheira/2018, FMDV/A/EGY/Kafr El-Sheikh/2018, FMDV/A/EGY/Kafr El-Sheikh/2022 and FMDV/A/EGY/Behiera/2022, were characterized on the basis of partial VP1 gene sequence analysis. The FMDV/SAT2/EGY/Beheira/2018 strain was clustered within the Lib-12 lineage of the topotype VII and shared 79.2–98.4% nucleotide identity with other Egyptian SAT2 strains available in Genbank database. On the other hand, the three FMDV serotype A sequences shared 74.4–99.1% nucleotide identity with each other. Also, they were phylogenetically classified within two distinct topotypes. The FMDV/A/Egy/Kafr El-Sheikh/2018 strain was grouped within the Asian topotype, meanwhile the FMDV/A/EGY/Kafr El-Sheikh/2022 and FMDV/A/EGY/Behiera/2022 strains were grouped together within the genotype IV of the African topotype. Interestingly, the deduced amino acid sequences of the four strains displayed numerous variations in comparison to the vaccine strains currently used in Egypt. In addition, most of these variations were present in prominent antigenic positions in the VP1 protein. These findings raise a crucial need to validate the protective potential of the vaccine strains against the newly emerging FMDV field strains and to update the vaccination strategy accordingly.

Lebertia litoralis sp. nov. a new water mite described on morphological and molecular characters (Acariformes, Hydrachnidia, Lebertiidae)

An integrative taxonomic approach, combining new morphological data with the analysis of partial COI sequences (DNA-barcodes) is used to describe Lebertia litoralis Zawal & Szenejko sp. nov. from lake habitats in Poland and Norway. The obtained DNA-barcodes of Polish and Norwegian specimens differ only slightly (k = 4.142, Π = 0.006). Morphologically, the new species is most similar to Lebertia porosa Thor, 1900 and L. obscura Thor, 1900, from which it differs by a slenderer shape of the first leg and the position of the distoventral setae of p-4, inserted rather far away from the distal segment edge. http://zoobank.org/urn:lsid:zoobank.org:pub:27F6FFD0-CA98-4FAD-BC16-58FA654E36ED

Partial sequence analysis of mitochondrial D-loop gene in tukong chicken

Abstract Tukong chicken is called the rumples (no tailbone) chicken in Indonesia. This research was done to determine whether the D-loop in mitochondrial DNA might be used to distinguish between the Tukong chicken and other local chickens. The D-loop region’s first 630 base pairs were amplified and successfully sequenced. Our research displayed 34 nucleotide variants based on the alignment between the Tukong and GenBank of Gallus (25 accession number) sequences of Indonesian local chicken and several exotic chicken breeds. However, there were no specific mutations for Tukong chicken. The Tajima’s neutrality test showed that from 31 sequences and 34 total sites, the nucleotide diversity (π) was 0.013. The phylogenetic analysis by the maximum-likelihood method revealed that the Tukong chicken was in a different clade from the Araucana, Nunukan, and Piao chickens, which have similar rumples phenotypes. Meanwhile, the local chicken of Indonesia (Kampung Sumatera, Pelung, Cemani, and Bekikuk) and the Tukong chicken are closely related. It can be concluded that based on the partial D-loop sequences, the Tukong chicken is more closely related to Indonesian local chicken despite its different morphological appearance.

Electricity Generation by a Phototrophic Bacterium in a Glucose−Fed Double Chambered Microbial Fuel Cell Using a Fabricated 3D Anode Electrode

Study’s Novelty/Excerpt This study presents an approach to enhancing microbial fuel cell (MFC) performance by employing phototrophic bacteria (PTB) and sustainable electrode materials, specifically a 3D anode electrode fabricated from reduced graphene oxide (rGO) and nickel (Ni) foam. By integrating morphological, biochemical, and molecular techniques to identify the electrochemically active PTB, the research achieved a significant eight-fold increase in power density using rGO-Ni electrodes compared to conventional Ni electrodes. This work underscores the potential of utilizing sustainable materials and PTB to improve MFC efficiency and economic viability, offering a promising direction for sustainable bioelectricity generation. Full Abstract Over the past years, despite intensified research on microbial fuel cells (MFC), low power densities were recorded, reducing the productivity and economic viability of the process. This necessitated testing various MFC configurations, fabricating various electrodes, and evaluating various substrate types and species of electrogenic microorganisms to improve MFC performance. Despite the dual advantage of phototrophic bacteria (PTB), metabolizing organic waste substances and generating electricity, less research was conducted on the bacterium. Although a significant amount of energy is generated using unsustainable (fossil-based) materials in electrode fabrication, this study focuses on using sustainable materials like carbon cloth and graphite to fabricate a 3D anode electrode to exploit the maximum energy generated by PTB. The PTB used in this study was identified through morphological characteristics and biochemical tests (catalase and oxidase) and confirmed using a molecular technique: 16S rRNA sequencing. Preliminary results indicated that the PTB was gram-negative, spherical in shape, non−motile, and facultatively anaerobic bacterium. Analysis of the 16S rRNA partial sequence was conducted in GenBank databases. 100 significant sequences with the lowest and highest similarities of 84.10% and 98.76% were recorded, respectively. Of these, 13 strains had the highest similarities of >90%, all belonging to the genus Dysgonomonas, with D. oryzarvi Dy73 (98.76%) as the closest. Reduced graphene oxide (rGO) used as the anode was prepared using Hummer’s method by depositing the rGO on nickel (Ni) foam which changed the colour of Ni from grey to black after depositing and annealing. In addition to the SEM images, which showed a continuous multi−layered 3D scaffold on the Ni, the cyclic voltammetry (CV) analyses indicated an increase in the electrochemical activities of the rGO−Ni electrode compared to Ni. The CV also confirmed the bacterium to be electrochemically active. The 100 mL glucose−fed two−chamber MFC were separately run with the Ni and rGO–Ni as anode electrodes in a batch mode for 11 days, while carbon cloth was used as the cathode for both runs. An approximate 0.58 W/m2 power density was recorded for Ni, but eight−fold of Ni’s, 4.9 W/m2was generated by rGO−Ni. The study demonstrated that using fabricated 3D rGO–Ni as anode electrode can increase the microbial adhesion and power density of bacterium in MFC, thereby providing a more applicable and sustainable alternative to bioelectricity generation.

Limosilactobacillus fermentum-derived silver nanoparticles: biosynthesis, optimization, and biological activities

AbstractProbiotic bacteria represent valuable sources of bioactive metabolites with diverse biological functions. This study focused on isolation and identification of promising probiotic isolates obtained from fermented dairy products, aiming to employ their capability for biosynthesizing silver nanoparticles (AgNPs) and to assess their biological activities. Among six probiotic examined isolates, isolate HwOs-2 exhibited the most promising characteristics, synthesizing spherical AgNPs ranging from 6 to 23 nm in size, as visualized by high-resolution transmission electron microscopy (HR-TEM). These nanoparticles displayed a negative zeta potential (−7.11 millivolts), effectively preventing aggregation. X-ray diffraction (XRD) analysis confirmed the crystalline nature of the AgNPs, revealing distinct diffraction peaks at specific 2θ angles (38.2°, 44.3°, 64.5°, and 77.4°) corresponding to the (111), (200), (220), and (311) planes of a face-centered cubic lattice. Fourier Transform Infrared Spectroscopy (FTIR) indicated the presence of organic coatings on the AgNPs, including proteins, amino acids, and carboxylic acids, potentially contributing to diverse biological activities. Isolate HwOs-2 was identified as Limosilactobacillus fermentum through Vitek2 automated system and 16 S rDNA partial sequence analysis. Furthermore, optimization of AgNP biosynthesis using response surface methodology (RSM) revealed the significant influence of silver nitrate solution volume, while pH and filtrate volume exhibit negligible effects and incubation time displays a curvature effect on AgNP production. Antibacterial assays against seven bacterial strains, encompassing both gram-positive and gram-negative species, demonstrated substantial antibacterial efficacy, with inhibition zones ranging from 20.3 to 27.6 mm against S. typhi and MRSA, respectively. Additionally, the AgNPs exhibited antitumor activity against Caco-2 and Huh-7 cell lines, with IC50 values of 350.08 and 388.35 µg/mL, respectively, while displaying lower cytotoxicity against normal (VERO) cells (IC50 value = 622.17 µg/mL). These findings underscore the biomedical potential of AgNPs produced by Limosilactobacillus fermentum across a spectrum of applications.

Characterization of Erwinia amylovora isolates from the northern region of Saudi Arabia, including CRISPR genotyping

AbstractFire blight, caused by the bacterium Erwinia amylovora, poses a global threat to the pome fruit industry, leading to reduced yields and significant economic losses. A comprehensive countrywide survey was carried out to determine the possible E. amylovora distribution in pome fruit‐growing regions. During the period 2020–2023, 85 isolates characteristic of E. amylovora were obtained from pear across 23 locations in three main pear‐producing regions (Al‐Jouf, Hail and Tabuk) in northern Saudi Arabia (SA). Isolates were identified using biochemical, molecular and pathogenicity assays. Molecular characterization of Saudi strains was achieved using partial 16S rRNA and rpoB gene sequencing, rep‐PCR (specifically, BOX‐PCR) and CRISPR array analysis. The CRISPR genotyping in particular, using an existing scheme of three CRISPR arrays, CR1, CR2 and CR3, provided consistent patterns of the Saudi isolates with high similarity to those of E. amylovora strains from the UK and France, hinting at a possible origin of the fire blight infections from these countries. Some variation was observed in patterns between local strains, highlighting the importance of continued surveillance and genetic studies for effective disease management strategies. Identification of fire blight in three regions over several years should serve as a warning to the Ministry of Environment, Water and Agriculture in Saudi Arabia, prompting the initiation of a more comprehensive survey and an active disease management programme. This programme should include early detection and advice to growers on prevention and control measures. This is the first scientific study on the occurrence and genetic variability of E. amylovora in Saudi Arabia.

Ochratoxin A Contamination of California Pistachios and Identification of Causal Agents.

Ochratoxin A (OTA) is a potent mycotoxin produced by Aspergillus and Penicillium spp., which contaminates many crops, including pistachios. Pistachios contaminated with OTA may be subjected to border rejections resulting in significant economic losses to the United States agricultural revenues. The current study examined prevalence of OTA in California-grown pistachios and identified its causal agents. OTA was detected in 20% of samples from 2018 to 2021 (n = 809), with 18% of samples exceeding the European Union regulatory limit of 5 μg/kg. Fungi potentially responsible for OTA contamination were isolated from leaves, nuts, and soil collected from 14 pistachio orchards across California. A total of 1,882 isolates of Aspergillus section Nigri and 85 isolates of section Circumdati were recovered. Within section Nigri, 216 (11.5%) isolates were identified as potential OTA producers using a boscalid-resistance assay. Phylogenetic analyses of partial gene sequences for β-tubulin and calmodulin genes resolved section Circumdati into four species: A. ochraceus (33%), A. melleus (28%), A. bridgeri (21%), and A. westerdijkiae (19%). A. westerdijkiae produced the highest levels of OTA in inoculated pistachios (47 μg/g), followed by A. ochraceus (9.6 μg/g) and A. melleus (3.3 μg/g). A. bridgeri did not produce OTA. OTA production by section Circumdati was optimal from 20 to 30°C. All 216 boscalid-resistant isolates from section Nigri were identified as A. tubingensis, and representative isolates (n = 130) produced 3.8 μg/kg OTA in inoculated pistachios. This is the first detailed report on OTA contamination and causal fungi in California pistachios and will be helpful in devising effective management strategies.