This study aimed to isolate and characterize endophytic bacteria from Panax vietnamensis Ha et Grushv., a rare medicinal ginseng species endemic to Vietnam. Several bacterial strains were isolated from root, stem, and leaf tissues, among which strain HS10, identified as Burkholderia sp., exhibited notable plant growth-promoting traits including indole-3-acetic acid (IAA) production, proteinase activity, and strong growth. Phylogenetic analysis based on 16S rRNA gene sequences confirmed the taxonomic placement of HS10 within the Burkholderia genus. IAA production was evaluated over a 5-day period with varying concentrations of L-tryptophan, revealing optimal production (46.61±5 µg/mL) on the fourth day at 0.1–0.15% tryptophan. Additionally, antibiotic susceptibility testing showed that HS10 was highly sensitive to cefadroxil and tetracycline, while resistant to cefpodoxime. These findings contribute to the understanding of the microbial diversity associated with P. vietnamensis and support the potential application of endophytic Burkholderia strains as biofertilizers to enhance sustainable ginseng cultivation medium.

Sâm Ngọc Linh (P.vietnamensis)- thảo dược quý ở Việt Nam và có chứa những chất hoạt tính sinh học. Một số loài vi khuẩn endophytic trên loài thực vật này cũng ảnh hưởng đến sâm. Trong đó, chủng Bacillus và Pseudomonas là các vi khuẩn endophytic chủ yếu trong quá trình phân lập Pseudomonas sp.HS6-2 được phân lập và tiến hành khảo sát một số đặc tính có thể ảnh hưởng đến sự sinh trưởng, phát triển và chất lượng của sâm Ngọc Linh. Kết quả chỉ ra vi khuẩn được phân lập nhạy cảm với các loại kháng sinh Cefadroxil, Tetraciline, Ampicilin, Amoxicillin, Cefpodoxim ở nồng độ 25 và 50 mg/ml, nhưng khi nồng độ kháng sinh này chạy đến 1000 mg/ml thì khả năng kháng kháng sinh của vi khuẩn bị biến mất. Một khả năng đặc biệt của vi khuẩn là sản xuất acid indole-3-acetic với nồng độ khá cao 116,74 ± 5,0 mg/ml khi khảo sát với nhiều nồng độ tryptophan có trong môi trường nuôi cấy.

A novel gliding, Gram-stain-negative, rod-shaped, strictly aerobic bacterium, designated SW4T, was isolated from seawater in the West Sea, Korea. Strain SW4T grew optimally at 30 °C, pH 7.5, and NaCl 2% on MA. Phylogenetic analysis based on the 16S rRNA gene placed strain SW4T in the genus Pontimicrobium within the family Flavobacteriaceae, with its closest relative being Pontimicrobium aquaticum KCTC 72003T (97.0% similarity). However, genome analysis revealed significant divergence, with average nucleotide identity (ANI) of 81.6% and digital DNA-DNA hybridization (dDDH) value of 24.4%, supporting its designation as a new species. The genome consists of a 3.44 Mb circular chromosome and a plasmid, with a G + C content of 32%. In addition to the physiological distinct characteristics, comparative genomic analysis identified unique genes associated with heavy metal transport, nitrogen and sulfur cycling, oxidative and osmotic stress responses, and numerous carbohydrate-active enzymes that are responsible for polysaccharide degradation and utilization, highlighting its marine adaptation. These findings differentiate strain SW4T from its closest and only existing species of P. aquaticum at both genomic and phenotypical levels. Based on phenotypic and phylogenetic evidence, we propose the novel species Pontimicrobium maritimus. sp. nov. with the type strain SW4T (= KCTC 42599T = InaCC B 1659T).

1-Deoxynojirimycin (DNJ) is a polyhydroxylated alkaloid with α-glucosidase inhibitory (AGI) activity, possessing potential as an anti-diabetes and anti-virus agent. In this study, Bacillus amyloliquefaciens TU11 showing AGI activity was isolated from a Vietnamese traditional soybean-fermented food, and its DNJ production was confirmed. The B. amyloliquefaciens TUN.327 mutant strain, which exhibits increased DNJ production, was obtained by subjecting the B. amyloliquefaciens TU11 strain to random mutagenesis using UV irradiation and N-methyl-N′-nitro-N-nitrosoguanidin treatment. To further enhance DNJ production, the effects of nine culture parameters and physical conditions were evaluated using the Plackett–Burman design. The results suggested that inoculum size, temperature, and FeSO4.7H2O were the most influential factors affecting DNJ production. Finally, the optimal culture conditions for maximizing DNJ concentration by B. amyloliquefaciens TUN.327 were predicted using Box–Behnken designs. Under the optimal culture conditions, B. amyloliquefaciens TUN.327 achieved a DNJ production of 2,167 ± 350 mg/L, which represents a ninefold increase compared to the wild-type TU11 cultured in the unoptimized medium (233 ± 30 mg/L).

The bacterial group of the phylum Bacteroidota greatly contributes to the global carbon cycle in marine ecosystems through its specialized ability to degrade marine polysaccharides. In this study, it is proposed that two novel facultative anaerobic strains, DS1-an-13321T and DS1-an-2312T, which were isolated from a sea squirt, represent a novel genus, Halosquirtibacter, with two novel species in the family Prolixibacteraceae. The 16S rRNA sequence similarities of these two strains were 91.26% and 91.37%, respectively, against Puteibacter caeruleilacunae JC036T, which is the closest recognized neighbor. The complete genomes of strains DS1-an-13321T and DS1-an-2312T each consisted of a single circular chromosome with a size of 4.47 and 5.19 Mb, respectively. The average amino acid identity and the percentage of conserved proteins against the type species of the genera in the family Prolixibacteraceae ranged from 48.33 to 52.35% and 28.34–37.37%, respectively, which are lower than the threshold for genus demarcation. Strains DS1-an-13321T and DS1-an-2312T could grow on galactose, glucose, maltose, lactose, sucrose, laminarin, and starch, and only DS1-an-2312T could grow on xylose and xylan under fermentation conditions. These strains produced acetic acid and propionic acid as the major fermentation products. Genome mining of the genomes of the two strains revealed 27 and 34 polysaccharide utilization loci, which included 155 and 249 carbohydrate-active enzymes (CAZymes), covering 57 and 65 CAZymes families, respectively. The laminarin-degrading enzymes in both strains were cell-associated, and showed exo-hydrolytic activity releasing glucose as a major product. The xylan-degrading enzymes of strain DS1-an-2312T was also cell-associated, and had endo-hydrolytic activities, releasing xylotriose and xylotetraose as major products. The evidence from phenotypic, biochemical, chemotaxonomic, and genomic characteristics supported the proposal of a novel genus with two novel species in the family Prolixibacteraceae, for which the names Halosquirtibacter laminarini gen. nov., sp. nov. and Halosquirtibacter xylanolyticus sp. nov. are proposed. The type strain of Halosquirtibacter laminarini is DS1-an-13321T (= KCTC 25031T = DSM 115329T) and the type strain of Halosquirtibacter xylanolyticus is DS1-an-2312T (= KCTC 25032T = DSM 115328T).

The insect larvae Protaetia brevitarsis seulensis have recently been researched as a nutritious food source and concentrated on their environmental impacts. Therefore, their gut microbiota has been studied to elucidate their effects and roles on the environment. Of the abundance of bacterial genus identified based on the 16S rRNA genes from isolates of the gut of insect larva Protaetia brevitarsis seulensis, six of the prominent genus were identified as Bacillus (40.2%), Cellulosimicrobium (33.5%), Microbacterium (2.8%), Streptomyces (3%), Krasilnikoviella (17.5%), and Isoptericola (3%) and their similarity of 16S rRNA blast changed from 99 to 100%. Cellulosimicrobium protaetiae BI34T showed strong denitrification and cellulose degradation activity. The newly complete genome sequence of BI34T and the genomes of five species was published in the genus Cellulosimicrobium with emphasis on the denitrification and secondary metabolite genes. In order to elucidate the relationship between the strain BI34T and the host insect larva, the whole-genome sequence was analyzed and compared with the genomes of five strains in the same genus, Cellulosimicrobium, loaded from GenBank. Our results revealed the composition of the gut microbiota of the insect larvae and analyzed the genomic data for the new strain to predict its characteristics and to understand the nitrogen metabolism pathway.

Methicillin-resistant Staphylococcus aureus (MRSA) is a critical pathogen responsible for a wide variety of serious infectious diseases in humans. The accelerated phenomena of drug tolerance, drug resistance, and dysbacteriosis provoked by antibiotic misuse are impeding the effectiveness of contemporary antibiotic therapies primarily used to treat this common worldwide pathogen. In this study, the antibacterial activity of 70% ethanol extract and multiple polar solvents of Ampelopsis cantoniensis were measured against the clinical MRSA isolate. The agar diffusion technique was employed to determine the zone of inhibition (ZOI), accompanied by the use of a microdilution series to identify the minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC). Our results revealed that the ethyl acetate fraction exhibited the most significant antibacterial activity, which was determined to be bacteriostatic based on the MBC/MIC ratio 8. A list of compounds isolated from A. cantoniensis was computationally studied to further investigate the mechanism of action with the bacterial membrane protein PBP2a. The combination of molecular docking and molecular dynamics methods showed that the main compound, dihydromyricetin (DHM), is expected to bind to PBP2a at allosteric site. In addition, DHM was identified as the major compound of ethyl acetate fraction, which accounts for 77.03 +/- 2.44% by high performance liquid chromatography (HPLC) analysis. As a concluding remark, our study addressed the antibacterial mechanism and suggested the prioritization of natural products derived from A. cantoniensis as a potential therapy for MRSA.Communicated by Ramaswamy H. Sarma

In the effort of isolating novel microbial species, the strain PL0132 T was isolated from a fallen leaf under fresh water at a stream, which glided when grown on a tap water medium (without nutrients). The strain was determined to be Gram-negative, strictly aerobic, and rod-shaped, which grew optimally at 25 °C, pH 6–7, and the strain tolerates 1% (w/v) NaCl concentration. The complete genome of strain PL0132 T comprises one contig with a sequencing depth of 76×, consisting of 8,853,064 base pairs and the genomic DNA G + C content was 46.7% (genome). 16S rRNA gene sequence analysis revealed that strain PL0132 T represents a member of the phylum Bacteroidetes and is affiliated with the genus Spirosoma . Based on genomic, phenotypic, and chemotaxonomic characteristics, the strain PL0132 T represents a novel species of the genus Spirosoma , for which the name Spirosoma foliorum sp. nov. is proposed (= KCTC 72228 T = InaCC B1447 T ).

The bacterium Neobacillus endophyticus BRMEA1T, isolated from the medicinal plant Selaginella involvens, known as its thermotolerant can grow at 50°C. To explore the genetic basis for its heat tolerance response and its potential for producing valuable natural compounds, the genomes of two thermotolerant and four mesophilic strains in the genus Neobacillus were analyzed using a bioinformatic software platform. The whole genome was annotated using RAST SEED and OrthVenn2, with a focus on identifying potential heat-tolerance-related genes. N. endophyticus BRMEA1T was found to possess more stress response genes compared to other mesophilic members of the genus, and it was the only strain that had genes for the synthesis of osmoregulated periplasmic glucans. This study sheds light on the potential value of N. endophyticus BRMEA1T, as it reveals the mechanism of heat resistance and the application of secondary metabolites produced by this bacterium through whole-genome sequencing and comparative analysis.

Multidrug resistance to pathogens has posed a severe threat to public health. The threat could be addressed by antimicrobial peptides (AMPs) with broad-spectrum suppression. In this study, Brevibacillus halotolerans 7WMA2, isolated from marine sediment, produced AMPs against Gram-positive and Gram-negative bacteria. The AMPs were precipitated by ammonium sulfate 30

A Gram-stain-negative, long rod, oxidase and catalase-positive strain WSW3-B12 T was isolated from red algae on tidal flats in the West Sea, Korea. Phylogenetic analysis based on the 16S rRNA gene sequence revealed that the strain WSW3-B12 T had the highest sequence similarity, 92.7%, to Flexithrix dorotheae DSM 6795 T , followed by Rapidithrix thailandica TISTR 1750 T at 90.8% in the family Flammeovirgaceae of the phylum Bacteroidota . The whole genome sequence determined using both the Nanopore and Illumina platforms revealed that the complete genome consists of 29 contigs, among which contig 1 was a circular chromosome, while the remaining 28 contigs were plasmids. The size of the genome was 10.1 Mbp and the G+C content was 34.1%. The average nucleotide identity (ANI), digital DNA–DNA hybridization (dDDH), average amino acid identity (AAI), and percentage of conserved proteins (POCP), phylogenomic-related indexes between the strain WSW3-B12 T and the closest strain Flexithrix dorotheae DSM 6795 T , were 76.6%, 19.9%, 57.2%, and 55.6%, respectively, which were all lower than the threshold values to support the creation of a novel genus. A comprehensive genome analysis revealed that the strain WSW3-B12 T harbored many of the key genes involved in central metabolism in the main chromosome and also carried important genes for the production of vitamins, quinone, and antimicrobial resistance on the plasmids. The strain also carried genes that are involved in the metabolism of heavy metals such as arsenic, cobalt, copper, and iron on both the chromosome and plasmids. Furthermore, the genome of the strain was highly enriched with carbohydrate-active enzymes (CAZymes), carrying a total of 241 CAZymes. Moreover, a complete CRISPR/Cas system was detected on plasmid 20. The major fatty acids of the strain were iso-C 15:0 and C 16:1 ω5. The polar lipids contained phosphatidylethanolamine, four unidentified lipids, and four glycolipids. The respiratory quinone was menaquinone 7. Based on the phenotypic, chemotaxonomic, and genomic analyses, the strain WSW3-B12 T could be assigned to a novel species and novel genus within the family Flammeovirgaceae , for which the name Chondrinema litorale gen. nov., sp. nov. (type strain WSW3-B12 T = KCTC 82707 T = GDMCC 1.3198 T ) is proposed.

The taxonomic relationship of Cellulosimicrobium fucosivorans SE3T and Cellulosimicrobium composti BIT-GX5T was re-evaluated. The type strains of the two species shared 99.9 % 16S rRNA gene sequence similarity, and whole genome sequence comparisons showed that the two species shared a 86.3 % digital DNA‒DNA hybridization (dDDH) value, a 98.5 % average nucleotide identity (ANI) score and a 98.2 % average amino acid identity (AAI) value. These values were higher than the recommend novel species recognition threshold values of 16S rRNA gene similarity of 98.6 %, dDDH cutoff value of 70 %, and ANI and AAI cutoff values of 95-96 %. In addition, the phylogenetic tree based on the 16S rRNA gene sequences as well as the phylogenomics tree based on whole genomes supported these two strains being closely related. Based on the principle of priority, we propose that Cellulosimicrobium fucosivorans is a later heterotypic synonym of Cellulosimicrobium composti.

Larvae live in soil have been well known for containing abundant microbiota in their gut. This study isolated six bacterial genera from the gut of larvae Protaetia brevitarsis seulensis including Bacillus, Cellulosimicrobium, Microbacterium, Streptomyces, Krasilnikoviella and Isoptericola based on specific media. Among these six genera, Cellulosimicrobium was collected for further analysis of cellulose-degrading features because of the most abundance and less studies up to now. Based on the 16S rDNA gene, the Cellulosimicrobium isolates were classified to C. cellulans, C. aquatile, C. funkei, C. protaetiae that were respectively isolated from four specific media such as modified ISP-2, MRS, modified anaerobic medium, modified fermentation medium. The analysis of their genome proved the presence of genes encoding for chitinases, alkyl resorcinol, and glucosidase in four strains. These cellulose degrading enzymes were useful for textile processing, paper recycling, production of nutritional supplements, food industry, production of alcohol from lignocellulosic materials, and beneficial microorganisms in denitrification and N-cycling in forest ecosystem as well as wastewater process.

Bacteroidota is a group of marine polysaccharide degraders, which play a crucial role in the carbon cycle in the marine ecosystems. In this study, three novel gliding strains, designated as SS9-22 T , W9P-11 T , and SW1-E11 T , isolated from algae and decaying wood were proposed to represent three novel species of the genus Fulvivirga . We identified a large number of genes encoding for carbohydrate-active enzymes, which potentially participate in polysaccharide degradation, based on whole genome sequencing. The 16S rRNA sequence similarities among them were 94.4–97.2%, and against existing species in the genus Fulvivirga 93.1–99.8%. The complete genomes of strains SS9-22 T , W9P-11 T , and SW1-E11 T comprised one circular chromosome with size of 6.98, 6.52, and 6.39 Mb, respectively; the GC contents were 41.9%, 39.0%, and 38.1%, respectively. The average nucleotide identity and the digital DNA-DNA hybridization values with members in the genus Fulvivirga including the isolates were in a range of 68.9–85.4% and 17.1–29.7%, respectively, which are low for the proposal of novel species. Genomic mining in three genomes identified hundreds of carbohydrate-active enzymes (CAZymes) covering up to 93 CAZyme families and 58–70 CAZyme gene clusters, exceeding the numbers of genes present in the other species of the genus Fulvivirga. Polysaccharides of alginate, chitin, laminarin, starch, and xylan were degraded in vitro, highlighting that the three strains are rich sources of CAZymes of polysaccharide degraders for biotechnological applications. The phenotypic, biochemical, chemotaxonomic, and genomic characteristics supported the proposal of three novel species in the genus Fulvivirga , for which the names Fulvivirga ulvae sp. nov. (SS9-22 T = KCTC 82072 T = GDMCC 1.2804 T ), Fulvivirga ligni sp. nov. (W9P-11 T = KCTC 72992 T = GDMCC 1.2803 T ), and Fulvivirga maritima sp. nov. (SW1-E11 T = KCTC 72832 T = GDMCC 1.2802 T ) are proposed.

A Gram-stain-negative and rod-shaped bacterial strain (WSW3-B6T) was isolated from red alga collected from the West Sea, Republic of Korea. Cells of strain WSW3-B6T were non-motile, aerobic and produced slightly yellow and mucoid colonies on marine agar. The strain grew optimally at 23-30 °C, with 0.5-4 % NaCl (w/v) and at pH 6.5-8.5. A phylogenetic analysis of the 16S rRNA gene revealed that strain WSW3-B6T belongs to the genus Flavobacterium within the family Flavobacteriaceae, having the highest sequence similarity to Flavobacterium arcticum SM1502T (96.7%), followed by Flavobacterium salilacus subsp. altitudinum LaA7.5T (96.2%) and Flavobacterium salilacus subsp. salilacus SaA2.12T (96.2%). The complete sequence of a circular chromosome of strain WSW3-B6T determined by combination of Oxford Nanopore and Illumina platforms comprised a total 2 725 095 bp with G+C content of 37.1 mol%. A comparative analysis based on the whole genome also showed the distinctiveness of strain WSW3-B6T. The average nucleotide identity (ANI) values between strain WSW3-B6T and the closest strains F. arcticum SM1502T, F. salilacus subsp. altitudinum LaA7.5T and F. salilacus subsp. salilacus SaA2.12T were 78.3, 77.8 and 77.7 %, respectively, while the digital DNA-DNA hybridization (dDDH) values between strain WSW3-B6T and the above closely related strains were 21.0, 20.4 and 20.3 %, respectively. Both the ANI and dDDH values supported the creation of a new species in the genus Flavobacterium. The major fatty acids (>10 %) were iso-C15 : 0 (19.3 %), C16 : 0 (14.0 %), iso-C17 : 0 3-OH (13.1 %) and C18 : 0 (10.7 %). The polar lipids of strain WSW3-B6T included phosphatidylethanolamine, three unidentified aminolipids and three unidentified lipids. Moreover, MK-6 was the only respiratory quinone. A comparison of the phylogenetic distinctiveness and the unique phenotypic and chemotaxonomic characteristics among strain WSW3-B6T and closely related type strains supported that strain WSW3-B6T (=KCTC 82708T=GDMCC 1.2627T) represents a novel species of the genus Flavobacterium, for which the name Flavobacterium litorale sp. nov. is proposed.

Bacillus species have been well-documented as bacteria isolated from soil with primary characteristics that were identified and applied to agriculture, wastewater treatment, pharmaceutic, and human life. This study focuses on the characterization of Bacillus strains isolated from a particular resource, which is seafood wastewater, and to list which correlating and different properties with those coming from soil. Of the 15 isolates obtained by positive Gram (+) screening, 14 sequenced Bacillus genomes type strain B. subtilis (B. subtilis) and Bacillus cereus (B. cereus), which were analyzed by the phylogenetic tree, were chosen for further investigation due to their majority. For antagonistic activity against E.coli ATCC 85922, no visible inhibitory zones were directly observed to isolates type strain B. cereus. On the other hand, out of the four B. subtilis exploited in this activity with AU > 200, only one exhibited a strong AU of 327. In the case of antibiotic susceptibility, B. subtilis was sensitive to most of the five antibiotics investigated in this study, particularly to the high coefficient of cell's susceptibility over 0.8 against penicillin and tetracyclin. Additionally, the critical property in biofilm production (elucidated isolates) was amplified with two genes abrB and spo0A, and was exhibited through SEM visualization. (c) 2021 Society of Chemical Industry (SCI).

The extensive usage of synthetic fungicides against fungal diseases has caused adverse impacts on both human and agricultural crops. Therefore, the current study aims to establish a new bacterium 7WMA2, as a biocontrol agent to achieve better antifungal results. The strain 7WMA2 was isolated from marine sediment, displayed a broad spectrum of several fungi that includes Alternaria alternata, Cladosporium sp., Candida albicans, Fusarium oxysporum, Trichosporon pullulans, and Trichophyton rubrum. The 16S rRNA phylogeny inferred that strain 7WMA2 was a member of Brevibacillus. The phylogenetic and biochemical analyses revealed that the strain 7WMA2 belongs to the species of Brevibacillus halotolerans. The complete genome sequence of Brevibacillus halotolerans 7WMA2 consists of a circular chromosome of 5,351,077 bp length with a GC content of 41.39 mol %, including 4433 CDS, 111 tRNA genes, and 36 rRNA genes. The genomic analysis showed 23 putative biosynthetic secondary metabolite gene clusters responsible for non-ribosomal peptides, polyketides and siderophores. The antifungal compounds concentrated from cell-free fermentation broth demonstrated strong inhibition of fungi, and the compounds are considerably thermal stable and adaptable to pH range 2-12. This complete genome sequence has provided insight for further exploration of antagonistic ability and its secondary metabolite compounds indicated feasibility as biological control agents against fungal infections.

A Gram-stain-positive, non-spore-forming, yellow-pigmented, non-motile, non-flagellated, facultative anaerobic and rod-shaped bacterial strain, designated BI34T, was isolated from the gut of the larva of Protaetia brevitarsis seulensis. Strain BI34T grew at 15-40 °C (optimum, 37 °C), at pH 6.5-9.0 (optimum, pH 7.5) and in the presence of 0-7 % (w/v) NaCl (optimum, 2 %). Based on the results of 16S rRNA gene sequence analysis, strain BI34T belonged to the phylum Actinobacteria and was closely related to Cellulosimicrobium funkei NBRC 104118T (99.3 %), Cellulosimicrobium cellulans NBRC 15516T (99.1 %), Cellulosimicrobium composti BIT-GX5T (99.0 %), Cellulosimicrobium fucosivorans SE3T (99.0 %), Cellulosimicrobium marinum NBRC 110994T (98.4 %) and Cellulosimicrobium terreum DS-61T (97.0 %). The genome to genome relatedness of the average nucleotide identity (ANI) and the digital DNA-DNA hybridization (dDDH) values calculated by the Genome-to-Genome Distance Calculator between strain BI34T and its related species mentioned above were lower than the threshold of 95 and 70 % for speciation, respectively. The predominant menaquinone of strain BI34T contained MK-9(H4), and the major fatty acids were anteiso-C15 : 0, C16 : 0 and anteiso-C17 : 0. Strain BI34T had diphosphatidylglycerol and phosphatidylglycerol as major polar lipids. The whole-cell sugars were galactose, glucose and ribose, and the cell-wall peptidoglycan contained lysine, alanine, aspartic acid and glutamic acid. The DNA G+C content of strain BI34T was 73.8 mol%. The difference in physiological and biochemical characteristics and the below-threshold values of genome-to-genome relatedness indicate that strain BI34T represents a novel species in the genus Cellulosimicrobium, for which the name Cellulosimicrobium protaetiae sp. nov. is proposed. The type strain is BI34T (=KCTC 49302T=NBRC 114073T).

Jejubacter calystegiae KSNA2T, a moderately halophilic, endophytic bacterium isolated from beach morning glory (Calystegia soldanella), was determined to be a novel species in a new genus in the family Enterobacteriaceae. To gain insights into the genetic basis of the salinity stress response of strain KSNA2T, we sequenced its genome using two complementary sequencing platforms (Illumina HiSeq and PacBio RSII). The genome contains a repertoire of metabolic pathways, such as those for nitrogen, phosphorus, and some amino acid metabolism pathways. Functional annotation of the KSNA2T genome revealed several genes involved in salt tolerance pathways, such as those encoding sodium transporters, potassium transporters, and osmoprotectant enzymes. Plant growth-promoting bacteria-based experiments indicated that strain KSNA2T promotes the germination of vegetable seeds in saline conditions. Overall, the genetic and biological analyses of strain KSNA2T provide valuable insights into bacteria-mediated salt tolerance in agriculture.

Co-culture of microalgae and microorganisms, supported with the resulting synergistic effects, can be used for wastewater treatment, biomass production, agricultural applications and etc. Therefore, this study aimed to explore the role of Bacillus subtilis (B. subtilis) in tolerance against the harsh environment of seafood wastewater, at which these microalgal-bacterial flocs were formed by microalgae cultivation. In this present study, B. subtilis isolated from the cultivation medium of Chlorella vulgaris and exposed to different salinity (0.1-4% w/v sodium chloride) and various pH range to determine the tolerant ability and biofilm formation. Interestingly, this bacteria strain that isolated from microalgae cultivation medium showed the intense viability in the salt concentration exceeding up to 4% (w/v) NaCl but demonstrated the decrease in cell division as environmental culture undergoing over pH 10. Cell viability was recorded higher than 71% and 92% for B. subtilis inoculum in media with salt concentration greater than 20 gL-1 and external pH 6.5-9, respectively. This showed that B. subtilis isolated from microalgal-bacteria cocultivation exhibited its tolerant ability to survive in the extremely harsh conditions and thus, mitigating the stresses due to salinity and pH.