Genome Length Research Articles

Characterization of the Mitochondrial Genome of Cambaroides schrenckii (Astacidea: Cambaridae) and Its Phylogenetic Implications

Background: Cambaroides schrenckii is an endangered freshwater crayfish in China, belonging to the genus Cambaroides, that can act as a complementary host for paragonimus. The objective of this study was to examine the complete mitochondrial genome characteristics and their evolutionary relationships within the Astacidea. Methods: The analysis of gene rearrangements and evolutionary relationships was conducted through the sequencing of the mitochondrial genome of C. schrenckii. Results: C. schrenckii mitochondrial genome length was 15,572, comprising thirteen PCGs, two rRNAs, 22 tRNAs, and one d-loop region of C. schrenckii. The mitochondrial genome of C. schrenckii exhibits an A + T content of 69.61% and a G + C content of 30.39%. Among the thirteen PCGs, cytb, nad3, and nad6 have a start codon of ATT, while the other ten PCGs have ATC, ATA, and ATG start codons. All 22 tRNA genes displayed a typical cloverleaf secondary structure. Gene rearrangement analysis showed that seven gene arrangements were identified based on PCGs in the infraorder Astacidea, with type I being the most common. Conclusions: The relationship between the American Cambaridae is closer to Astacidae than the Asian Cambaridae. The present study provides a theoretical basis for further discussions of developmental relationships in the infraorder Astacidea.

Signature of viral fossils: a comparative genomics approach to understand the diversity of endogenous retroviruses in bats

Endogenous retroviruses (ERVs) are traces of past viral infections commonly found in vertebrate genomes. Many ERVs are tightly regulated by the host genomes and co-opted for various functions within the hosts. Bats are the only true volant mammals, with the smallest mammalian genomes and a high fraction of ERVs within the genomes. They are important hosts for various zoonotic viral pathogens and can effectively modulate their immune response to tolerate viral infections. Integrations of retroviruses have been implicated as one of the mechanisms by which bats have co-evolved strategies to combat viral infections. In this study, we investigated the diversity of ERVs in over 40 publicly available bat genomes to understand the distribution and the evolution of ERVs within bats. We observed all classes of ERVs within bat genomes including even the complex lenti retroviruses. Alpha and spuma retroviruses which are generally considered rare in mammals, were common within bats. We observed a positive correlation between bat genome size and length of ERV elements. Interestingly, nearly 30 % of the ERVs within bats are intact suggesting a recent origin or co-option by the host genome. Future studies focusing on comparative genomic and experimental data will be critical to understand the role of these ERVs in host genome evolution.

NDM-1 and KPC-3 co-producing Klebsiella pneumoniae ST512 in bronchial secretion from a patient in an intensive care unit of a Greek Tertiary Care Hospital.

This study investigated a strain of Klebsiella pneumoniae, identified as GRTHES, which exhibited extensive antibiotic resistance. The strain was resistant to all beta-lactams, including combinations withnewer agents such as meropenem/vaborbactam and imipenem/relebactam, as well as to aminoglycosides, fluoroquinolones, fosfomycin, trimethoprim-sulfamethoxazole and colistin. It remained susceptible to tigecycline. Whole-genome sequencing was performed by Ion Torrent platform on the K.pneumoniae strain. Genomic analysis revealed a genome length of 5,808,650 bp and a GC content of 56.9%. Advanced sequencing techniques and bioinformatic tools were used to assess resistance genesand plasmid replicons, highlighting the emergence of multidrug resistance and virulence traits. Thestrain carried blaNDM-1 and blaKPC-3 genes and was designated to KL107 O2afg type. Colistin resistance-associated mgrB/pmrB gene mutations were present, and the strain also harbored yersiniabactin-encoding ybt gene. Our findings provide insights into the genomic context of blaNDM-1 and blaKPC-3 carbapenemase-producing K. pneumoniae and emphasize the importance of continuous surveillance and novel therapeutic strategies to combat multidrug-resistant bacterial infections. It is the first time that an NDM-1 and KPC-3 co-producing strain of K. pneumoniae ST512 is identified in Greece. This study highlights the essential role of genomic surveillance as a proactive strategy to control the spread of carbapenemase-producing K. pneumoniae isolates, particularly when key antimicrobial resistance genes, such as blaNDM-1 and blaKPC-3, are plasmid-mediated. Detailed characterization of these isolates could reveal plasmid similarities that facilitate adaptation and transmission within and between hospitals. Although data on patient movements are limited, it is plausible that carbapenem-resistant isolate was selected to co-produce KPC and NDM through plasmid acquisition.

Genetic differentiation of Oncomelania hupensis robertsoni in hilly regions of China: Using the complete mitochondrial genome.

Oncomelania hupensis robertsoni is the only intermediate host of Schistosoma japonicum in hilly regions of south-west China, which plays a key role during the transmission of Schistosomiasis. This study aimed to sequence the complete mitochondrial genome of Oncomelania hupensis robertsoni and analyze genetic differentiation of Oncomelania hupensis robertsoni. Samples were from 13 villages in Yunnan Province of China, with 30 Oncomelania hupensis snails per village, and the complete mitochondrial genome was sequenced. A comprehensive analysis of the genetic differentiation of Oncomelania hupensis robertsoni was conducted by constructing phylogenetic trees, calculating genetic distances, and analyzing identity. A total of 26 complete mitochondrial sequences were determined. The length of genome ranged from 15,181 to 15,187 bp, and the base composition of the genome was A+T (67.5%) and G+C content (32.5%). This genome encoded 37 genes, including 13 protein-coding genes, 2 rRNA genes, and 22 tRNA genes. The phylogenetic trees and identity analysis confirmed that Oncomelania hupensis robertsoni was subdivided into Oncomelania hupensis robertsoni Yunnan strain and Sichuan strain, with a genetic distance of 0.0834. Oncomelania hupensis robertsoni Yunnan strain was further subdivided into two sub-branches, corresponding to "Yunnan North" and "Yunnan South", with a genetic distance of 0.0216, and the samples exhibited over 97% identity. Oncomelania hupensis robertsoni is subdivided into Oncomelania hupensis robertsoni Yunnan strain and Sichuan strain. Oncomelania hupensis robertsoni Yunnan strain exhibits a higher level of genetic identity and clear north-south differentiation. This work reported the first mitochondrial genome of Oncomelania hupensis robertsoni Yunnan strain, which could be used as an important reference genome for Oncomelania hupensis, and also provide the important information for explaining the distribution pattern of Oncomelania hupensis robertsoni and control of Schistosoma japonicum.

Complete genome sequence of Bacillus pumilus NWMCC0302, a strain for degrading bovine blood

BackgroundDirectly discharging livestock and poultry slaughter blood without proper treatment can cause severe ecological damage. Exploring the use of microorganisms to break down waste blood into smaller molecules such as peptides and amino acids, as well as investigating the possibility of transforming these small molecules into water-soluble fertilizers containing amino acids, holds significant research value in the comprehensive utilization of livestock and poultry blood.ResultsIn this study, a single strain of Bacillus pumilus NWMCC0302, which has effectively degraded bovine blood, was isolated from abattoir blood sludge using casein agar plates and Columbia blood agar plates. The degradation test was carried out using bovine raw blood as a nitrogen source in the medium, and the results showed that the strain degraded 53.83% of bovine blood under optimal degradation conditions. The whole genome sequencing of Bacillus pumilus NWMCC0302 was conducted using the second-generation DNBSEQ platform and the third-generation PacBio platform, employing high-throughput sequencing technology. The size of the strain's entire genome was determined to be 3 868 814 bp with a G-C content of 41.63%. The total gene length accounted for 88.98% of the genome length at 3 442 341 bp and encoded 4 113 genes. The strain contained 79 tRNAs, 24 rRNAs, 7 sRNAs, and 296 repetitive sequences. The gene data obtained from sequencing were also functionally annotated using the COG, KEGG, and VFDB databases. In the COG database, 310 genes were involved in amino acid transport and metabolism, including 10 catabolic proteins related to COGs. In the KEGG database, were 201 genes involved in amino acid metabolism pathways, including 8 genes in nitrogen metabolism pathways and 2 genes in oxidative pathways. The VFDB database contains two lysostaphin genes and one serine protease-hydrolyzed ClpP gene.ConclusionsIn summary, Bacillus pumilus NWMCC0302 was screened for its efficient ability to degrade bovine blood. Additionally, the genetic information of Bacillus pumilus NWMCC0302 was revealed at the genetic level, providing a feasible experimental method for applying this strain to the degradation of blood from slaughtered livestock and poultry. Moreover, it is a potential functional strain for producing amino acid-containing water-soluble fertilisers.

Discovery of Alanomyces manoharacharyi: A Novel Fungus Identified Using Genome Sequencing and Metabolomic Analysis.

In this study, a new species of Alanomyces was isolated as an endophyte from the bark of Azadirachta indica from Mulshi, Maharashtra. The identity of this isolate was confirmed based on the asexual morphological characteristics as well as multi-gene phylogeny based on the internal transcribed spacer (ITS) and large subunit (LSU) nuclear ribosomal RNA (rRNA) regions. As this was the second species to be reported in this genus, we sequenced the genome of this species to increase our knowledge about the possible applicability of this genus to various industries. Its genome length was found to be 35.01 Mb, harboring 7870 protein-coding genes as per Augustus and 8101 genes using GeMoMa. Many genes were annotated using the Clusters of Orthologous Groups (COGs) database, the Kyoto Encyclopedia of Genes and Genomes (KEGG), Gene Ontology (GO), Swiss-Prot, NCBI non-redundant nucleotide sequences (NTs), and NCBI non-redundant protein sequences (NRs). The number of repeating sequences was predicted using Proteinmask and RepeatMasker; tRNA were detected using tRNAscan and snRNA were predicted using rfam_scan. The genome was also annotated using the Pathogen-Host Interactions Database (PHI-base) and AntiSMASH. To confirm the evolutionary history, average nucleotide identity (ANIb), phylogeny based on orthologous proteins, and single nucleotide polymorphisms (SNPs) were carried out. Metabolic profiling of the methanolic extract of dried biomass and ethyl acetate extract of the filtrate revealed a variety of compounds of great importance in the pharmaceutical and cosmetic industry. The characterization and genomic analysis of the newly discovered species Alanomyces manoharacharyi highlights its potential applicability across multiple industries, particularly in pharmaceuticals and cosmetics due to its diverse secondary metabolites and unique genetic features it possesses.

Genome assembly at chromosome scale with telomere ends for Pearlspot, Etroplus suratensis

The pearlspot, Etroplus suratensis is a climate resilient cichlid fish that exhibits unusual adaptation to salinity. The fish is able to complete full life cycle in diverse salinity habitats ranging from fresh water to marine environments. High-quality primary and phased genome assemblies were generated for pearlspot fish using PacBio HiFi and Arima HiC sequencing technologies, for the first time. The primary assembly is highly contiguous with contig N50 length of 36 Mb. The final assembly is of 1.247 Gb with N50 length of 51.57 Mb and 98% of the genome length anchored to 24 chromosomes. The genome was assessed to be 99.9% complete based on BUSCO evaluation and was predicted to contain 52.96% repeat elements. We have predicted 27,192 protein encoding genes, of which 21,580 were functionally annotated. The genome offers an invaluable resource to understand adaptation of pearlspot fish to diverse salinity habitats.

The Transcriptional Gradient in Negative-Strand RNA Viruses Suggests a Common RNA Transcription Mechanism.

We introduce a novel model of nonsegmented negative-strand RNA virus (NNSV) transcription. Previous models have relied on polymerase behavioral differences in the highly conserved intergenic sequences. Our model hypothesizes the transcriptional gradient in NNSVs is explained through a simple model with two parameters associated with the viral polymerase. Most differences in expression can be attributed to the processivity of the polymerase while additional attenuation occurs in the presence of overlapping genes. This model reveals a correlation between polymerase processivity and genome length, which is consistent with the universal entry of polymerases through the 3' end of the genome. Using this model, it is now possible to predict the transcriptional behavior of NNSVs from genotype alone, revolutionizing the design of novel NNSV variants for biomedical applications.

The chloroplast genome sequence and phylogenetic analysis of Rubia alata Wall and Rubia ovatifolia Z. Ying Zhang. (Rubiaceae).

Rubia alata Wall (R. alata) and Rubia ovatifolia Z. Ying Zhang (R. ovatifolia) are unique medicinal plants native to China. Sequencing their chloroplast genomes is important for understanding species differentiation and establishing phylogenetic relationships. The chloroplast genomes of R. alata and R. ovatifolia were sequenced using the Illumina HiSeq platform. The chloroplast genome of R. alata is 154,973 base pairs (bp) in length, containing a large single-copy region (LSC) of 84,801bp, a small single-copy region (SSC) of 17,138bp, and a pair of inverted repeats (IRs) of the same length. The length of the chloroplast genome, LSC, SSC, and IR regions of R. ovatifolia is 26,517bp, 84,716bp, 17,116bp and 26,517bp, respectively. Codon usag e analysis revealed that R. alata had the highest frequency of Aspartic acid (Asp) (1650 occurrences) in protein-coding sequences (CDS), while R. ovatifolia showed the highest frequency of Tyrosine (Try) (1479 occurrences). Comparative analysis of chloroplast genomes across seven species from the genus Rubia identified the most divergent coding regions, including rps16, psbI-trns-CGA, and petN, while plastid rRNAs were the most conserved. Phylogenetic analysis showed R. alata clustering with R. cordifolia (66.3% support), and R. ovatifolia clustering with Rubia podantha (100% support). These findings enhance our understanding of the chloroplast genome structure in Rubia species and provide molecular information for the future development and utilization of R. alata and R. ovatifolia resources.

Characterization of two lytic bacteriophages infecting carbapenem-resistant clinical Klebsiella pneumoniae in Dhaka, Bangladesh

Bacteriophages or bacteria infecting viruses are genetically diverse. Due to the emergence of antimicrobial-resistant bacteria, lytic bacteriophages are gaining enormous attention for treating superbug infections. Klebsiella pneumoniae is one of the eight most significant nosocomial pathogens and is addressed as a critical priority pathogen by WHO, requiring alternative treatment options. We reported two highly lytic bacteriophages, Klebsiella phage Kpn BM7 and the novel Klebsiella phage Kpn BU9, isolated from hospital wastewater and exhibiting lytic activity against different clinical isolates. Whole-genome analysis revealed that phages BM7 and BU9 belong to class Caudoviricetes. Phage BM7, with a genome length of 170,558 bp, is a member of the genus Marfavirus and the species Marfavirus F48. While phage BU9, with a genome length of 60,450 bp, remains unclassified. Neither phage harbors any lysogenic, toxin, or antimicrobial resistance genes. Both phages can steadily survive up to 40 °C and at pH 5–7. The optimal MOI was 0.1 for BM7 and 1 for BU9, with short latent periods of 10 and 25 min and burst sizes of 85 PFU/cell and 12 PFU/cell, respectively. This is the first carbapenem-resistant K. pneumoniae targeting lytic phages to be reported from Bangladesh. This study suggests that BM7 and BU9 are potential candidates for targeting carbapenem-resistant K. pneumoniae.

Aegilops crassa Cytotypes in Some Regions of Türkiye.

A new hexaploid cytotype of Aegilops crassa has been identified in Türkiye. To assess the ploidy levels of native populations, 50 samples from Adıyaman, Batman, Bitlis, Diyarbakır, Hakkari, Mardin, Siirt, Şanlıurfa, Şırnak, and Van were analyzed using flow cytometry and cytogenetic techniques. DNA content was determined by comparison with standard plants. Results confirmed two cytotypes in Türkiye: tetraploid populations from Batman, Bitlis, Diyarbakır, Hakkari, Mardin, Siirt, Şanlıurfa, and Şırnak, and hexaploid accessions from Adıyaman and Van. Ten metaphase plates were analyzed. The tetraploid cytotype exhibited chromosome lengths of 8.95 ± 0.27 to 13.96 ± 0.13 µm, a total genome length of 165.51 ± 0.34 µm, and nuclear DNA content of 18.53 ± 0.29 to 20.37 ± 0.49 pg. Most chromosomes were metacentric, except for chromosomes 7, 8, 10, and 12, which were submetacentric. Two satellite pairs were found on chromosomes 4 and 10. The hexaploid cytotype showed chromosome lengths of 8.90 ± 0.16 to 14.06 ± 0.06 µm, a total genome length of 230.47 ± 0.23 µm, and nuclear DNA content of 33.40 ± 0.52 to 35.01 ± 0.31 pg. Most chromosomes were also metacentric, with three satellite pairs on chromosomes 3, 6, and 10. In conclusion, both tetraploid (2n = 2x = 28) and hexaploid (2n = 6x = 42) cytotypes of Ae. crassa exist in Türkiye, with the hexaploid cytotype having potential for wheat breeding programs.

The complete mitochondrial genome of Dimorphopterus japonicus (Hidaka, 1959) (Hemiptera, Lygaeoidea) and phylogenetic relationships within the Lygaeoidea superfamily

Dimorphopterus japonicus is a kind of pest which seriously harms sorghum and millet. In this study, we sequenced the mitochondrial whole genome of D. japonicus (Hidaka, 1959), and characterized and analyzed the mitogenome. The D. japonicus genome length is 15,473 bp, and it exhibits a typical high A + T content (77.6%). The mitogenomic structure of D. japonicus is highly conservative and there are no gene rearrangements. The evolutionary rates of the PCGs are in the order of atp8 > nad3 > nad6 > nad2 > nad5 > atp6 > nad4 > nad4L > cox2 > nad1 > cytb > cox3 > cox1. By using the Bayesian inference and maximum likelihood methods, we inferred the phylogenetic relationships within Lygaeoidea and estimated their divergence times based on concatenated mitogenome genes. The stable clades of (Oxycarenidae + Piesmatidae), (Malcidae + Colobathristidae), (Meschiidae + Berytidae), and (Blissidae+(Cymidae + Ninidae)) were consistently recovered in all analyses. Estimated divergence times revealed that the divergence time of the Lygaeoidea was 99.4 Ma (95% HPD: 83.4-124.8 Ma), and most lygaeoid families diverged during the early Cretaceous to late Paleogene. Berytidae is the latest differentiation in the lygaeoid families, and the genus Dimorphopterus was differentiated in 45.9 Ma (95% HPD: 39.8–47.7 Ma). This study is of great significance for reconstructing the phylogeny of Lygaeoidea and providing insights into its evolutionary history.

The complete mitochondrial genome of Sicista caudata Thomas, 1907 (Rodentia: Sicistidae) and its phylogenetic analyses

This study aimed to examine the complete mitogenome sequence of Sicista caudata Thomas, 1907. A circular double-stranded structure made up the mitochondrial genome of S. caudata. The complete length of the mitochondrial genome was 16,629 bp. The mitochondrial genome of S. caudata included 13 protein-coding genes, one control region, 22 tRNA genes, two rRNA genes, and one origin of L-strand replication. S. caudata was supported by bootstrap values of 100%. This study verified the evolutionary status of S. caudata in the Superfamily Dipodoidea at the molecular level.

The complete chloroplast genome of Hemiboea subacaulis var. jiangxiensis Z. Y. Li 1983 (Gesneriaceae), an endemic species in China

The complete chloroplast genome of a Chinese endemic species Hemiboea subacaulis var. jiangxiensis was reported and characterized. The length of chloroplast genome is 153,311 bp, with 37.6% GC content. It has a typical quadripartite structure, including a large single-copy region (LSC, 84,287 bp), a small single-copy region (SSC, 18,094 bp) and a pair of inverted repeats (IRs, 25,465 bp). Totally, 133 unique genes were predicted, including 88 protein-coding genes, 37 tRNA genes and eight rRNA genes. Phylogenetic analysis and genetic distance revealed this species is sister to its typic H. subacaulis var. subacaulis. This study offers novel genetic data for the molecular identification and phylogenetic analysis of the Hemiboea.

Genomic analysis and characterization of lytic bacteriophages that target antimicrobial resistant Escherichia coli in Addis Ababa, Ethiopia

The emergence of antibiotic resistance in E. coli strains has sparked a fervent investigation of alternative therapies, such as the use of lytic bacteriophages. Phage genome sequence analysis is a novel method for learning more about proteins and other biomolecules encoded by phages, particularly phage-lytic enzymes that are crucial to the lysis of bacterial cells. Seven potential lytic E. coli phages—EH-B-A (A1), EP-M-A, EP-B-K (E2), EI-SP-GF, ET-SD-TH, and ST-TK—isolated from activated dairy farm sludges, rivers, and hospital liquid waste genomes were described in this study. The Illumina NextSeq 550 sequencer was used for sequencing phage isolates. The virus nucleotide collection (nr/nt) (taxid:10239) was used to evaluate whole-genome sequences. Phylogenetic analysis was performed using the MEGA11 software. Genome sequencing revealed that each bacteriophage contained a linear double-stranded DNA genome. Phage isolates were taxonomically identified as the Caudoviricetes class with four genera of phages, including Kagunavirus, Vequintavirus, Dhillonvirus, and Jilinvirus. Phage genome lengths varied from 24,264 to 136,204 bp, and GC contents ranged from 44 % to 55 %. In total, 33–218 CDSs (coding sequences) were predicted, with 19–77 % of CDSs encoding functional proteins. All phages lacked tRNA genes in their genomes, except for EI-SP-GF, which possessed five tRNA genes. Based on the phylogenetic tree analysis, the phage isolates were related to Enterobacteria and E. coli phage sequences in the database. Screening did not show any genes encoding for a CRISPR-like system, virulence, antibiotic resistance, or lysogeny. Because of their stringent lytic nature, these phage isolates might be used in the future to treat E. coli infections. This study might also provide some primary data for developing phage control techniques and advance our understanding of the genetic composition of E. coli phages.

Mitochondrial genome of the Indian spot-billed duck and its phylogenetic and conservation implications.

The Indian spot-billed duck, Anas poecilorhyncha is a large dabbling and non-migratory breeding bird. The identification and phylogenetic relationship of A. poecilorhyncha remain uncertain due to the presence of overlapping meristic characters and hybridization with closely related species. Molecular data aids when there are challenges in morphological identification. However, genetic characterization of A. poecilorhyncha has been paid less attention. Apart from their functional and physiological role, mitochondrial genome can also be used for various purposes, including species identification, phylogenetic analysis, understanding the domestication history of species etc. Therefore, the present study aimed to sequence the mitochondrial genome of A. poecilorhyncha and its closely related domestic species A. platyrhynchos (mallard duck) to understand their mitochondrial genome structure and phylogenetic relationships. The length of mitochondrial genome of A. poecilorhyncha and A. platyrhynchos was 16,608 and 16,604bp respectively. Mitochondrial genome contained 37 genes and a non-coding control region. Overall, the characteristics of mitochondrial genome of both species were found to be conserved. The phylogenetic tree exhibited seven major clades (A to G) with a high bootstrap support. Notably, the Indian A. poecilorhyncha population formed a distinct clade (C) whereas the A. poecilorhyncha that were probably sampled from China grouped along with A. zonorhyncha (clade B). Besides, one of the A. poecilorhyncha probably sampled from China was placed in the clade A, which predominantly consisted of A. platyrhynchos. It suggests that Indian A. poecilorhyncha population is genetically different from Chinese A. poecilorhyncha population. Further, it sheds light on the importance of conducting a comprehensive phylogenetic study on these species. The newly sequenced mitochondrial genome of A. poecilorhyncha and A. platyrhynchos would be useful not only to have a better understanding of the phylogeny and evolution of Anas species but also to help in the conservation of A. poecilorhyncha which is under constant threat from rapid urbanization, interspecific hybridization and other human activities.

The genome sequence of the corn cockle, Agrostemma githago L., 1753 (Caryophyllaceae)

We present a genome assembly from an individual Agrostemma githago (the corn cockle; Tracheophyta; Magnoliopsida; Caryophyllales; Caryophyllaceae). The genome sequence has a total length of 1,735.0 megabases. Most of the assembly is scaffolded into 24 chromosomal pseudomolecules suggesting the individual is a tetraploid (2n = 4x = 48). The organelle genomes have been assembled, and the length of the mitochondrial genome is 262.91 and the plastid genome 151.73 kilobases in length. Gene annotation of this assembly on Ensembl identified 38,816 protein-coding genes.

The complete mitochondrial genome of the endangered Atlantic Pygmy Devil Ray, Mobula hypostoma (Bancroft, 1831), from Brazil.

Mobulidae is a monophyletic family within the Myliobatiformes that comprises pelagic species represented by manta and devil rays. Among the genus Mobula, the Atlantic Pygmy Devil Ray - Mobula hypostoma - is reported in coastal regions exclusively in tropical and subtropical Atlantic Ocean from 1 to 100m deep. In Brazil, M. hypostoma is one of the least studied Mobula species. It is regularly misidentified, especially as Mobula thurstoni, and is commonly listed as bycatch, in fishery inventories, or related to opportunistic sightings in the national territory. Here, we describe the complete nucleotide sequence of the mitochondrial genome (mitogenome) from Mobula hypostoma, which is 18,141bp in length and comprises 13 protein-coding, two ribosomal RNA, and 22 transfer RNA genes. The M. hypostoma mitochondrial genes organisation and mitochondrial genome length are similar to other Mobula species, and the phylogenetic reconstruction indicates M. hypostoma as closely related to Mobula munkiana. The Brazilian mitogenome of M. hypostoma is expected to be a valuable resource for molecular-based species identification, and evolutionary and phylogeography studies.

Wildlife Infection of Peste des Petits Ruminants Detected in China, 2024.

In 2013, the second outbreak of peste des petits ruminants occurred in China, leading to a spillover in more than 20 provinces and municipalities over the next few months. Thereafter, the epidemic situation was stable owing to strict prevention and control measures. In February 2024, several bharals and argali with suspected symptoms of PPR were discovered in Rutog country, Tibet Autonomous Region. Samples collected from these animals were delivered to our laboratory for diagnosis; the results of fluorescence quantitative reverse-transcription (RT) PCR indicated that all samples were positive for PPR viral RNA. The N and F gene fragments were amplified successfully via RT-PCR, and these results confirmed that these animals were infected with PPRV. A PPRV strain (subsequently named ChinaTibet2024) was sequenced, and its genome length was 15,954 nucleotides. A phylogenetic tree analysis using N and F genes and viral genomes showed that the ChinaTibet2024 genome was classified into lineage IV of the PRRV genotypes. The genome of the ChinaTibet2024 strain was found to be closely related to PPRVs isolated in China between 2013 and 2014. A base insertion and a base deletion were detected in the M gene 5' untranslated region. Results indicated that the prevalent PPRV strains in China did not show significant changes and that special attention should be paid to the surveillance of wild animals as an important part of PPR prevention and control.

Construction of core genome multi-locus sequence typing schemes for population structure analyses of Nocardia species

Nocardia, a member of the Actinobacteria phylum, populates diverse habitats globally, with certain species being the cause of various clinical infections in humans. There is paucity of data regarding the population structure of this genus and of established genomic-based phylogenetic methods. We examined the whole genome sequences of 193 isolates spanning five major pathogenic Nocardia species sourced from public databases, encompassing diverse geographic regions. Using the chewBBACA pipeline, a species-specific core genome multilocus sequence typing (cgMLST) schema was created for N. cyriacigeorgica, N. farcinica, N. brasiliensis, N. wallacei, and N. abscessus. Additional genomic features that were examined included virulence factor (VF) profile, total length and open-reading frame count, the core genome length and core gene count, and GC content. Our findings indicated that: (i) N. brasiliensis diverges significantly from the other four species, underscoring its distinct evolutionary trajectory; (ii) the population structures of all species were polyclonal, with phylogenetic clustering occurring in the minority of isolates; (iii) clonal complexes were largely restricted to specific geographical locations, rather than demonstrating a global distribution, and (iv) initial evidence suggests no direct common-source transmission amongst the studied strains. Our study establishes a comprehensive genome-based phylogenetic methodology for population structure of Nocardia species.