A bacterial strain, designated ASS-1T, was isolated and identified from a sediment sample of the river Ganges, Allahabad, India. The strain was Gram-stain-negative, formed straw-yellow pigmented colonies, was strictly aerobic, motile with a single polar flagellum, and positive for oxidase and catalase. The major fatty acids were C16 : 1ω7c/ 16 : 1 C16 : 1ω6c, C18 : 1ω7c and C16 : 0. Sequence analysis based on the 16S rRNA gene revealed that strain ASS-1T showed high similarity to Pseudomonas guguanensis CC-G9AT (98.2 %), Pseudomonas alcaligenes ATCC 14909T (98.2 %), Pseudomonas oleovorans DSM 1045T (98.1 %), Pseudomonas indolxydans IPL-1T (98.1 %) and Pseudomonas toyotomiensis HT-3T (98.0 %). Analysis of its rpoB and rpoD housekeeping genes confirmed its phylogenetic affiliation and showed identities lower than 93 % with respect to the closest relatives. Phylogenetic analysis based on the 16S rRNA, rpoB, rpoD genes and the whole genome assigned it to the genus Pseudomonas . The results of digital DNA–DNA hybridization based on the genome-to-genome distance calculator and average nucleotide identity revealed low genome relatedness to its close phylogenetic neighbours (below the recommended thresholds of 70 and 95 %, respectively, for species delineation). Strain ASS-1T also differed from the related strains by some phenotypic characteristics, i.e. growth at pH 5.0 and 42 °C, starch and casein hydrolysis, and citrate utilization. Therefore, based on data obtained from phenotypic and genotypic analysis, it is evident that strain ASS-1T should be regarded as a novel species within the genus Pseudomonas , for which the name Pseudomonas fluvialis sp. nov. is proposed. The type strain is ASS-1T (=KCTC 52437T=CCM 8778T).

The macroalgae surface allows specific bacterial communities to colonize, resulting in complex biological interactions. In recent years, several researchers have studied the diversity and function of the epiphytic bacteria associated with algal host, but largely these interactions remain underexplored. In the present study we analysed the cultivable diversity and polymer degradation potential of epiphytic bacteria associated with five different marine macroalgae (Sargassum, Ulva, Padina, Dictyota and Pterocladia sp.) sampled from the central west coast of India. Out of the total 360 strains isolated, purified and preserved, about 238 strains were identified through 16S rRNA gene sequence analysis and processed for polymer (cellulose, pectin, xylan and starch) degrading activities. Phylogeny placed the strains within the classes Actinobacteria, Bacilli, Alpha-proteobacteria, and Gamma-proteobacteria and clustered them into 45 genera, wherein Vibrio, Bacillus, Pseudoalteromonas, Alteromonas, Staphylococcus and Kocuria spp. were the most abundant with 20 strains identified as potentially novel taxa within the genera Bacillus, Cellulosimicrobium, Gordonia, Marinomonas, Vibrio, Luteimonas and Pseudoalteromonas. In terms of polymer hydrolysis potential, 61.3% had xylanase activity, while 59.7%, 58.8%, and 52.2% had amylase, cellulase, and pectinase activity, respectively. Overall, 75.6% of the strains degraded more than one polysaccharide, 24% degraded all polymers, while nine strains (3.8%) degraded raw sugarcane bagasse. This study showed great potential for seaweed-associated bacteria in the bio-remediation of agro-waste based raw materials, which can be employed in the form of green technology.

While studying culturable bacterial diversity in different marine habitats of the central west coast of India, two novel Gram-stain-positive, strictly aerobic, motile, endospore-forming and rod-shaped bacterial strains designated as SAOS 44T and SAB 38T were isolated from mangrove sediment soil and the surface of a macroalga, respectively. The strains were taxonomically characterized by using a polyphasic approach and genomic methods. The phylogenetic analysis based on 16S rRNA gene sequencing placed the strains firmly in the genus Domibacillus and were most closely related to Domibacillus antri KCTC 33636T. The predominant fatty acids were iso-C15 : 0 and anteiso-C15 : 0. The major polar lipids were diphosphatidylglycerol and phosphatidylglycerol in addition to an aminophosphoglycolipid. MK-6 was the only respiratory quinone. The range of values of digital DNA–DNA hybridization (19.2–24.9 %) and the ortho-average nucleotide identity (74.1–81.4 %) among strains SAOS 44T, SAB 38T and other Domibacillus species clearly supports their status as a distinct and novel species for which the names Domibacillus mangrovi sp. nov. SAOS 44T (=DSM 100930T=KCTC 33820T=MTCC 12571T) and Domibacillus epiphyticus sp. nov. SAB 38T (=DSM 100929T=KCTC 33830T=MTCC 12575T) are proposed, respectively.

A novel archaeal strain designated as SPP-AMP-1(T) was isolated from saltpan soil, using the serial dilution method on a halophilic archaeal medium supplemented with ampicillin. Cells were both rod-shaped and pleomorphic in nature, non-motile, unable to produce acid from a variety of sugars or grow anaerobically with different substrates (L-arginine) and electron acceptors (DMSO, nitrate). Optimal growth was observed at 42 degrees C, 3.4-4.2 M NaCl and pH 7.2. Cells did not lyse in distilled water and grew in the absence of Mg2+ ions. Phylogenetic analysis based on the sequences of 16S rRNA gene, amino acid sequence of beta'-subunit of RNA polymerase and 400 conserved proteins retrieved from the whole genome assemblies showed that strain SPP-AMP-1(T) was distantly related to any existing genera within the family Halobacteriaceae. MK-8 was the only quinone detected. Polar lipid analysis showed a unique combination of diethyl derivatives of phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester, glycosyl-mannosyl-glucosyl diether and sulphated glycosyl-mannosyl-glucosyl diether as the major lipids. The G+C content of genomic DNA is 57.7 mol%. The phenotypic, phylogenetic and genomic data supported the concept of the novel genus status of strain SPP-AMP-1(T) in the family Halobacteriaceae for which the name Halocatena pleomorpha gen. nov., sp. nov., is proposed; the type strain is SPP-AMP-1(T) (=JCM 31368(T)=KCTC 4276(T)=MTCC 12579(T)).

A pink-pigmented, Gram-stain-positive, aerobic, coccoid-shaped bacterial strain, designated as S5-TSA-19T, was isolated from an explosives contaminated site in Panchkula, Haryana, India. The 16S rRNA gene sequencing blast analysis indicated that the strain is a member of the family Planococcaceae with the highest sequence similarity to Planomicrobium soli XN13T (96.1 %), followed by Planococcus maitriensis S1T (95.6 %), Planococcus plakortidis DSM 23997T (95.6 %), Planomicrobium flavidum ISL-41T (95.6 %), Planococcus rifietoensis M8T (95.5 %), Planococcus salinus LCB217T (95.5 %) and Planococcus maritimus DSM 17275T (95.5 %). Phylogenetic analysis based on 16S rRNA gene and whole-genome sequences (based on a conserved set of 400 proteins) retrieved the strain in a distinct branch indicating a separate lineage within the family Planococcaceae . Strain S5-TSA-19T had a distinctive chemotaxonomic pattern comprising A4α type peptidoglycan based on l-Lys-d-Asp, iso-C15 : 0 as the major fatty acid, absence of phosphatidylethanolamine as a major lipid and MK-7 and MK-6 as the major menaquinones, differentiating it from the genera Planococcus and Planomicrobium , thus supporting the findings of molecular phylogeny. Further, strain S5-TSA-19T was able to biotransform hexahydro-1,3,5,-trinitro-1,2,5-triazine (RDX) into nitrite derivatives under aerobic conditions in 2–4 days, whereas the closest reference strains did not possess this property. On the basis of polyphasic taxonomic characterization and a phylogenomics approach, strain S5-TSA-19T is proposed as the type strain of a novel species in a novel genus for which the name Indiicoccus explosivorum gen. nov., sp. nov. is proposed (=JCM 31737T=KCTC 33871T=MTCC 12608T).