First report on in-depth genome and comparative genome analysis of a metal-resistant bacterium Acinetobacter pittii S-30, isolated from environmental sample.

A newly isolated bacterium Acinetobacter pittii S-30 was recovered from waste-contaminated soil in Ranchi, India. The isolated bacterium belongs to the ESKAPE organisms which represent the major nosocomial pathogens that exhibit high antibiotic resistance. Furthermore, average nucleotide identity (ANI) analysis also showed its closest match (>95%) to other A. pittii genomes. The isolate showed metal-resistant behavior and was able to survive up to 5 mM of ZnSO4. Whole genome sequencing and annotations revealed the occurrence of various genes involved in stress protection, motility, and metabolism of aromatic compounds. Moreover, genome annotation identified the gene clusters involved in secondary metabolite production (biosynthetic gene clusters) such as arylpolyene, acinetobactin like NRP-metallophore, betalactone, and hserlactone-NRPS cluster. The metabolic potential of A. pittii S-30 based on cluster of orthologous, and Kyoto Encyclopedia of Genes and Genomes indicated a high number of genes related to stress protection, metal resistance, and multiple drug-efflux systems etc., which is relatively rare in A. pittii strains. Additionally, the presence of various carbohydrate-active enzymes such as glycoside hydrolases (GHs), glycosyltransferases (GTs), and other genes associated with lignocellulose breakdown suggests that strain S-30 has strong biomass degradation potential. Furthermore, an analysis of genetic diversity and recombination in A. pittii strains was performed to understand the population expansion hypothesis of A. pittii strains. To our knowledge, this is the first report demonstrating the detailed genomic characterization of a heavy metal-resistant bacterium belonging to A. pittii. Therefore, the A. pittii S-30 could be a good candidate for the promotion of plant growth and other biotechnological applications.

Discovery of novel treponemes associated with pododermatitis in elk (Cervus canadensis).

Pododermatitis, also known as treponeme-associated hoof disease (TAHD), presents a significant challenge to elk (Cervus canadensis) populations in the northwestern USA, with Treponema spp. consistently implicated in the lesion development. However, identifying species-specific Treponema strains from these lesions is hindered by its culture recalcitrance and limited genomic information. This study utilized shotgun sequencing, in silico genome reconstruction, and comparative genomics as a culture-independent approach to identify metagenome-assembled Treponema genomes (MATGs) from skin scraping samples collected from captive elk experimentally challenged with TAHD. The genomic analysis revealed 10 new MATGs, with 6 representing novel genomospecies associated with pododermatitis in elk and 4 corresponding to previously identified species-Treponema pedis and Treponema phagedenis. Importantly, genomic signatures of novel genomospecies identified in this study were consistently detected in biopsy samples of free-ranging elk diagnosed with TAHD, indicating a potential etiologic association. Comparative metabolic profiling of the MATGs against other Treponema genomes showed a distinct metabolic profile, suggesting potential host adaptation or geographic uniqueness of these newly identified genomospecies. The discovery of novel Treponema genomospecies enhances our understanding of the pathogenesis of pododermatitis and lays the foundation for the development of improved molecular surveillance tools to monitor and manage the disease in free-ranging elk.IMPORTANCETreponema spp. play an important role in the development of pododermatitis in free-ranging elk; however, the species-specific detection of Treponema from pododermatitis lesions is challenging due to culture recalcitrance and limited genomic information. The study utilized shotgun sequencing and in silico genome reconstruction to identify novel Treponema genomospecies from elk with pododermatitis. The discovery of the novel Treponema species opens new avenues to develop molecular diagnostic and epidemiologic tools for the surveillance of pododermatitis in elk. These findings significantly enhance our understanding of the genomic landscape of the Treponemataceae consortium while offering valuable insights into the etiology and pathogenesis of emerging pododermatitis in elk populations.

In-depth genome and pan-genome analysis of a metal-resistant bacterium Pseudomonas parafulva OS-1.

A metal-resistant bacterium Pseudomonas parafulva OS-1 was isolated from waste-contaminated soil in Ranchi City, India. The isolated strain OS-1 showed its growth at 25-45°C, pH 5.0-9.0, and in the presence of ZnSO4 (upto 5 mM). Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain OS-1 belonged to the genus Pseudomonas and was most closely related to parafulva species. To unravel the genomic features, we sequenced the complete genome of P. parafulva OS-1 using Illumina HiSeq 4,000 sequencing platform. The results of average nucleotide identity (ANI) analysis indicated the closest similarity of OS-1 to P. parafulva PRS09-11288 and P. parafulva DTSP2. The metabolic potential of P. parafulva OS-1 based on Clusters of Othologous Genes (COG) and Kyoto Encyclopedia of Genes and Genomes (KEGG) indicated a high number of genes related to stress protection, metal resistance, and multiple drug-efflux, etc., which is relatively rare in P. parafulva strains. Compared with other parafulva strains, P. parafulva OS-1 was found to have the unique ß-lactam resistance and type VI secretion system (T6SS) gene. Additionally, its genomes encode various CAZymes such as glycoside hydrolases and other genes associated with lignocellulose breakdown, suggesting that strain OS-1 have strong biomass degradation potential. The presence of genomic complexity in the OS-1 genome indicates that horizontal gene transfer (HGT) might happen during evolution. Therefore, genomic and comparative genome analysis of parafulva strains is valuable for further understanding the mechanism of resistance to metal stress and opens a perspective to exploit a newly isolated bacterium for biotechnological applications.

Phylogeny and evolution of SARS-CoV-2 during Delta and Omicron variant waves in India.

SARS-CoV-2 evolution has continued to generate variants, responsible for new pandemic waves locally and globally. Varying disease presentation and severity has been ascribed to inherent variant characteristics and vaccine immunity. This study analyzed genomic data from 305 whole genome sequences from SARS-CoV-2 patients before and through the third wave in India. Delta variant was reported in patients without comorbidity (97%), while Omicron BA.2 was reported in patients with comorbidity (77%). Tissue adaptation studies brought forth higher propensity of Omicron variants to bronchial tissue than lung, contrary to observation in Delta variants from Delhi. Study of codon usage pattern distinguished the prevalent variants, clustering them separately, Omicron BA.2 isolated in February grouped away from December strains, and all BA.2 after December acquired a new mutation S959P in ORF1b (44.3% of BA.2 in the study) indicating ongoing evolution. Loss of critical spike mutations in Omicron BA.2 and gain of immune evasion mutations including G142D, reported in Delta but absent in BA.1, and S371F instead of S371L in BA.1 could explain very brief period of BA.1 in December 2021, followed by complete replacement by BA.2. Higher propensity of Omicron variants to bronchial tissue, probably ensured increased transmission while Omicron BA.2 became the prevalent variant possibly due to evolutionary trade-off. Virus evolution continues to shape the epidemic and its culmination.Communicated by Ramaswamy H. Sarma.

Biochemical, functional and genomic characterization of a new probiotic Ligilactobacillus salivarius F14 from the gut of tribes of Odisha.

Characterization of new potential probiotics is desirable in the field of research on probiotics for their extensive use in health and disease. Tribes could be an unusual source of probiotics due to their unique food habits and least dependence on medications and consumption of antibiotics. The aim of the present study is to isolate lactic acid bacteria from tribal fecal samples of Odisha, India, and characterize their genetic and probiotic attributes. In this context one of the catalase-negative and Gram-positive isolates, identified using 16S rRNA sequencing as Ligilactobacillus salivarius, was characterized in vitro for its acid and bile tolerance, cell adhesion and antimicrobial properties. The whole genome sequence was obtained and analyzed for strain level identification, presence of genomic determinants for probiotic-specific features, and safety. Genes responsible for its antimicrobial and immunomodulatory functions were detected. The secreted metabolites were analyzed using high resolution mass spectroscopy; the results indicated that the antimicrobial potential could be due to the presence of pyroglutamic acid, propionic acid, lactic acid, 2-hydroxyisocaproic acid, homoserine, and glutathione, and the immuno-modulating activity, contributed by the presence of short chain fatty acids such as acetate, propionate, and butyrate. So, to conclude we have successfully characterized a Ligilactobacillus salivarius species with potential antimicrobial and immunomodulatory ability. The health-promoting effects of this probiotic strain and/or its derivatives will be investigated in future.

Influence of Geochemistry in the Tropical Hot Springs on Microbial Community Structure and Function.

Thermophiles inhabiting high temperatures are considered primitive microorganisms on early Earth. In this regard, several works have demonstrated microbial community composition in geothermal environments. Despite that, studies on hot springs located in the Indian subcontinent viz., Surajkund in the district Hazaribag, Jharkhand; Bakreshwar in the district Birbhum, West Bengal; Tantloi in the district Dumka, and Sidpur in the district Pakur, Jharkhand are scanty. Nonetheless, the metagenomic analysis of these hot springs showed significant differences in the predominant phyla corresponding to geochemical properties. The Chloroflexi, Proteobacteria, Actinobacteria, Deinococcus-Thermus, and Firmicutes were dominant phyla in all the samples. In contrast, Meiothermus was more in comparatively low-temperature hot springs. In addition, archaeal phyla, Euryarchaeota, Candidatus Bathyarchaeota, and Crenarchaeota were predominant in all samples. The canonical correspondence analysis (CCA) showed the abundance of Deinococcus, Thermus, Pyrobaculum, Kocuria, and Geodermatophilus positively correlated with the aqueous concentration of sulfate, fluoride, and argon in relatively high-temperature (≥ 72 °C) hot springs. However, at a lower temperature (≤ 63 °C), Thermodesulfovibrio, Caldilinea, Chloroflexus, Meiothermus, and Tepidimonas are positively correlated with the concentration of zinc, iron, and dissolved oxygen. Further, hierarchical clustering exhibits variations in its functional attributes depending on the temperature gradients. Metagenome analysis predicted carbon, methane, sulfur, and nitrogen metabolism genes, indicating a wide range of bacteria and archaea habitation in these hot springs. In addition, identified several genes encode polyketide biosynthesis pathways. The present study described the microbial community composition and function in the tropical hot springs and their relationship with the environmental variables.

Pan-genome evolution and its association with divergence of metabolic functions in Bifidobacterium genus.

Previous studies were mainly focused on genomic evolution and diversity of type species of Bifidobacterium genus due to their health-promoting effect on host. However, those studies were mainly based on species-level taxonomic resolution, adaptation, and characterization of carbohydrate metabolic features of the bifidobacterial species. Here, a comprehensive analysis of the type strain genome unveils the association of pan-genome evolution with the divergence of metabolic function of the Bifidobacterium genus. This study has also demonstrated that horizontal gene transfer, as well as genome expansion and reduction events, leads to the divergence of metabolic functions in Bifidobacterium genus. Furthermore, the genome-based search of probiotic traits among all the available bifidobacterial type strains gives hints on type species, that could confer health benefits to nutrient-deficient individuals. Altogether, the present study provides insight into the developments of genomic evolution, functional divergence, and potential probiotic type species of the Bifidobacterium genus.

Phylogenomic Analysis of Metagenome-Assembled Genomes Deciphered Novel Acetogenic Nitrogen-Fixing Bathyarchaeota from Hot Spring Sediments.

This study describes the phylogenomic analysis and metabolic insights of metagenome-assembled genomes (MAGs) retrieved from hot spring sediment samples. The metagenome-assembled sequences recovered three near-complete genomes belonging to the archaeal phylum. Analysis of genome-wide core genes and 16S rRNA-based phylogeny placed the ILS200 and ILS300 genomes within the uncultivated and largely understudied bathyarchaeal phylum, whereas ILS100 represented the phylum Thaumarchaeota. The average nucleotide identity (ANI) of the bin ILS100 was 76% with Nitrososphaeria_archaeon_isolate_SpSt-1069. However, the bins ILS200 and ILS300 showed ANI values of 75% and 70% with Candidatus_Bathyarchaeota_archaeon_isolate_DRTY-6_2_bin_115 and Candidatus_Bathyarchaeota_archaeon_BA1_ba1_01, respectively. The genomic potential of Bathyarchaeota bins ILS200 and ILS300 showed genes necessary for the Wood-Ljungdahl pathway, and the gene encoding the methyl coenzyme M reductase (mcr) complex essential for methanogenesis was absent. The metabolic potential of the assembled genomes included genes involved in nitrogen assimilation, including nitrogenase and the genes necessary for the urea cycle. The presence of these genes suggested the metabolic potential of Bathyarchaeota to fix nitrogen under extreme environments. In addition, the ILS200 and ILS300 genomes carried genes involved in the tricarboxylic acid (TCA) cycle, glycolysis, and degradation of organic carbons. Finally, we conclude that the reconstructed Bathyarchaeota bins are autotrophic acetogens and organo-heterotrophs. IMPORTANCE We describe the Bathyarchaeota bins that are likely to be acetogens with a wide range of metabolic potential. These bins did not exhibit methanogenic machinery, suggesting methane production may not occur by all subgroup lineages of Bathyarchaeota. Phylogenetic analysis support that both ILS200 and ILS300 belonged to the Bathyarchaeota. The discovery of new bathyarchaeotal MAGs provides additional knowledge for understanding global carbon and nitrogen metabolism under extreme conditions.

Genome analysis of Pseudomonas species reveals that Pseudomonas panacis Park et al. 2005 is a later heterotypic synonym of Pseudomonas marginalis (Brown 1918) Stevens 1925 (Approved Lists 1980).

We described the comparative genomic analysis of Pseudomonas panacis DSM 18529T and Pseudomonas marginalis DSM 13124T of the genus Pseudomonas to define the taxonomic assignment. When conducting this analysis, genomic information for 203 type strains was available in the NCBI genome database. The ANI, AAI and isDDH data were higher than the threshold values between Pseudomonas panacis DSM 18529T and Pseudomonas marginalis DSM 13124T. Whole-genome comparisons show 97 % average nucleotide identity, 98 % average amino acid identity and 75 % in silico DNA-DNA hybridization values. Pseudomonas marginalis (Brown 1918) Stevens 1925 (Approved Lists 1980) have priority over the name Pseudomonas panacis Park et al. 2005, therefore nomenclatural authorities propose that Pseudomonas panacis Park et al. 2005 is a later heterotypic synonym of Pseudomonas marginalis (Brown 1918) Stevens 1925 (Approved Lists 1980). The type strain is ATCC 10844T (=DSM 13124T=NCPPB 667T).

Pufferfish (Tetraodon cutcutia) Sampled from a Freshwater River Serves as an Intermediate Reservoir of a Sucrose Nonfermenting Variant of Vibrio cholerae PS-4.

We describe the genomic characteristics of Vibrio cholerae strain PS-4 that is unable to ferment sucrose on a thiosulfate citrate bile salt sucrose (TCBS) agar medium. This bacterium was isolated from the skin mucus of a freshwater pufferfish. The genome of strain PS-4 was sequenced to understand the sucrose nonfermenting phenotype. The gene encoding the sucrose-specific phosphotransferase system IIB (sucR) was absent, resulting in the defective sucrose fermenting phenotype. In contrast, genes encoding the glucose-specific transport system IIB (ptsG) and fructose-specific transport system IIB (fruA) showed acid production while growing with respective sugars. The overall genome relatedness indices (OGRI), such as in silico DNA-DNA hybridization (isDDH), average nucleotide identity (ANI), and average amino acid identity (AAI), were above the threshold value, that is, 70% and 95 to 96%, respectively. Phylogenomic analysis based on genome-wide core genes and the nonrecombinant core genes showed that strain PS-4 clustered with Vibrio cholerae ATCC 14035T. Further, genes encoding cholera toxin (ctx), zonula occludens toxin (zot), accessory cholera enterotoxin (ace), toxin-coregulated pilus (tcp), and lipopolysaccharide biosynthesis (rfb) were absent. PS-4 showed hemolytic activity and reacted strongly to the R antibody. Therefore, the Vibrio cholerae from the pufferfish adds a new ecological niche of this bacterium. IMPORTANCE Vibrio cholerae is native of aquatic environments. In general, V. cholerae ferments sucrose on thiosulfate citrate bile salt sucrose (TCBS) agar and produces yellow colonies. V. cholerae strain PS-4 described in this study is a sucrose nonfermenting variant associated with pufferfish skin and does not produce yellow colonies on TCBS agar. Genes encoding sucrose-specific phosphotransferase system IIB (sucR) were absent. The observed phenotype in the distinct metabolic pathway indicates niche-specific adaptive evolution for this bacterium. Our study suggests that the nonfermenting phenotype of V. cholerae strains on TCBS agar may not always be considered for species delineation.

Description of Acinetobacter kanungonis sp. nov., based on phylogenomic analysis.

A novel strain of a member of the genus Acinetobacter, strain PS-1T, was isolated from the skin of fresh water pufferfish (Tetraodon cutcutia) collected from Mahanadi River, India. Cells were Gram-stain-negative, aerobic, coccoid and non-motile. The predominant polar lipids were diphosphatidylglycerol (DPG), phosphatidylglycerol (PG), phosphatidylethanolamine (PE) and phospholipid (PL) and the cell wall sugars were glucose, galactose and ribose. The major cellular fatty acids of PS-1T were C18 : 1ω9c (30.67 %), C16 : 1ω7c (19.54 %), C16 : 0 (15.87 %), C12 : 0 (7.35 %) and C12 : 0 3-OH (6.77 %). The genome size was 3.5 Mbp and the DNA G+C content was 41.97 %. Gene ontology study revealed that the major fraction of genes were associated with biological processes (53.99 %) followed by molecular function (30.42 %) and cellular components (15.58 %). Comparisons of 16S rRNA gene sequences revealed 97.94-97.05 % sequence similarity with the closely related type strains of species of the genus Acinetobacter. The average nucleotide identity (ANI) and average amino acid identity (AAI) of PS-1T with reference strains of species of the genus Acinetobacter with validly published names were bellow 95-96 and the corresponding in-silico DNA-DNA hybridization (DDH) values were below 70 %. A phylogenomic tree based on core genome analysis supported these results. Genotypic and phenotypic characteristics of PS-1T indicate that the strain represents a novel species of the genus Acinetobacter and the name Acinetobacter kanungonis sp. nov. is proposed. The type strain is PS-1T (=JCM 34131T=NCIMB 15260T).

Phylogenomic Analysis Reveals That Arthrobacter mysorens Nand and Rao 1972 (Approved Lists 1980) and Glutamicibacter mysorens Busse 2016 are Later Heterotypic Synonyms of Arthrobacter nicotianae Giovannozzi-Sermanni 1959 (Approved Lists 1980) and Glutamicibacter nicotianae Busse 2016.

We described the comparative genomic analysis to delineate the taxonomic relationship between the two Glutamicibacter species Glutamicibacter mysorens NBRC 103060T and Glutamicibacter nicotianae NBRC 14234T. Phylogenetic tree based on concatenated ribosomal protein marker genes showed both species clade together. The average nucleotide identity (ANI) values between G. mysorens NBRC 103060T and G. nicotianae NBRC 14234T ranged from 97.23 to 97.97%. Further, the average amino acid identity (AAI) between two strains were more than 97.61%. The ANI, AAI and in silico DNA-DNA hybridization (isDDH) data were higher than the threshold value for bacterial species delineation. The two strains have identical profile of fatty acids, sugars and lipid composition; and overall similar phenotypic characteristics. It therefore becomes evident that the two species actually belong to the same species. Arthrobacter nicotianae (Giovannozzi-Sermanni 1959) (Approved Lists 1980) and Glutamicibacter nicotianae Busse 2016 have priority over the names Arthrobacter mysorens (Nand and Rao 1972) (Approved Lists 1980) and Glutamicibacter mysorens Busse 2016, therefore we proposed that Glutamicibacter mysorens Busse 2016 is a later heterotypic synonym of Glutamicibacter nicotianae Busse 2016. The type strain is ATCC 15236T = CCM 1648T = BCRC (formerly CCRC) 11219T = CCUG 23842T = CDA 883T = CIP 82.107T = DSM 20123T = HAMBI 1859T = IAM 12342T = IFO (now NBRC) 14234T = IMET 10353T = JCM 1333T = LMG 16305T = NCIMB 9458T = NRIC 0153T.

Composition and functional characterization of the gut microbiome of freshwater pufferfish (Tetraodon cutcutia).

This study describes the community composition and functions of the gut microbiome of the freshwater omnivorous pufferfish based on metagenomic approach. Metagenome sequence data showed a dominance of the class Gammaproteobacteria followed by Fusobacteria, Actinobacteria, Anerolineae, Betaproteobacteria, Deinococci, Clostridia and Deltaproteobacteria. At the order level, the most abundant groups were Aeromonadales, Fusobacteriales, Enterobacterales, Synechococcales. The genus Aeromonas was the most predominant followed by Plesiomonas and Cetobacterium. Additionally, within the domain Archaea, class Methanomicrobia was most abundant followed by Hadesarchaea, Thermoplasmata, Candidatus Altiarchaeales, Candidatus Bathyarchaeota and Thermoprotei. The metabolic profile of the bacterial community exhibited a high prevalence of genes associated with core housekeeping functions, such as synthesis of cofactors, vitamins, prosthetic groups, pigments, amino acids and its derivatives, carbohydrate and protein metabolism. Comparative analysis with other fish gut microbiome showing similarity in protein metabolism with carnivorous Salmon and carbohydrate metabolism with herbivorous grass carp respectively. This study describes the bacterial community compositions are influenced by the trophic level.

Draft Genome Sequences of Vibrio alginolyticus Strain S6-61 and Vibrio diabolicus Strain S7-71, Isolated from Corals in the Andaman Sea.

We report the draft genome sequences of Vibrio alginolyticus strain S6-61 and Vibrio diabolicus strain S7-71, isolated from the corals Pocillopora verrucosa and Fungia danai, respectively. The genomes of strains S6-61 and S7-71 contain 4,880 and 4,641 protein coding genes, respectively, and harbor genes associated with the ectoine biosynthesis pathway.

Draft Genome Sequence of Microbacterium oryzae Strain MB-10, Isolated from a Rice Field in India.

We report the draft genome sequence of Microbacterium oryzae strain MB-10T, which was isolated from rice field soil. The genome is 3.04 Mb, with a G+C content of 71.10%, and encodes 2,727 proteins. The genome sequence provides further information about strain MB-10T and the genus Microbacterium.

Draft Genome Sequence of Idiomarina sp. Strain W-5T, Isolated from the Andaman Sea.

Here, we report the draft genome sequence of Idiomarina sp. strain W-5T, which was isolated from the Andaman Sea. The genome encodes 2,207 proteins. The Idiomarina sp. strain W-5T whole-genome sequence will help us to understand the metabolic diversity in marine bacteria.

Draft Genome Sequences of Two Vibrio fortis Strains Isolated from Coral (Fungia sp.) from the Andaman Sea.

We report the draft genome sequences of Vibrio fortis strains AN-60 and S7-72, which were isolated from coral (Fungia sp.) from the Andaman Sea. The genome sizes for strains AN-60 and S7-72 are 5.43 and 5.53 Mb, respectively. Both strains harbor genes associated with protocatechuate and azathioprine degradation and the sulfate reduction pathway.

Glutamicibacter mishrai sp. nov., isolated from the coral Favia veroni from Andaman Sea.

A novel aerobic marine actinobacterium (strain S5-52T) belonging to the genus Glutamicibacter was isolated from the coral Favia veroni sampled from the Andaman Sea, India. Cells are Gram stain positive and rod shaped. The DNA G+C content was 58.7 mol%. The major quinones were MK-8 and MK-9. The polar lipids were diphosphatidylglycerol, phosphatidylglycerol, glycolipid, trimannosyldiacylglycerol, phospholipid and dimannosylglyceride. The peptidoglycan type was A4α. Strain S5-52T showed a maximum 16S rRNA similarity of 99.36% with Glutamicibacter halophytocola DSM 101718T. The genome of strain S5-52T was 3.57 Mb that contains 3274 protein coding sequences (CDS). DNA-DNA similarity and ANI values between S5-52T and the reference strains were below 70% and 95-96%, respectively. Analysis of genomic reduction events in the evolutionary path from the LUCA (last universal common ancestor) to G. mishrai LMG 29155T and G. halophytocola DSM 101718T exhibit a number of genes involved in amino acid metabolism, cell wall biogenesis and replication, recombination and repair mechanism that reduced in both the species. Based on phenotypic, chemotaxonomic properties and comparative genomic studies, the strain S5-52T is considered a novel species of the genus Glutamicibacter, for which the name Glutamicibacter mishrai sp. nov. is proposed. The type strain is S5-52T (= KCTC 39846T = LMG 29155T).

Variation in synonymous codon usage in Paenibacillus sp. 32O-W genome.

Paenibacillus sp. 32O-W, which is attributed for biodesulfurization of petroleum, has 56.34% genomic G+C content. Correspondence analysis on Relative Synonymous Codon Usage (RSCU) of the Paenibacillus sp. 32O-W genome has revealed the two different trends of codon usage variation. Two sets of genes have been identified representing the two distinct pattern of codon usage in this bacterial genome. We have measured several codon usage indices to understand the influencing factors governing the differential pattern of codon usage variation in this bacterial genome. We also observed significant differences in many protein properties between the two gene sets (e.g., hydrophobicity, protein biosynthetic cost, protein aggregation propensity). The compositional difference between the two sets of genes and the difference in their potential gene expressivity are the driving force for the differences in protein biosynthetic cost and aggregation propensity. Based on our results we argue that codon usage variation in Paenibacillus sp. 32O-W genome is actually influenced by both mutational bias and translational selection.