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Microbially synthesized nanoparticles has received increasing attentions owing to the broad applications in biology and medicine. In this study, we report a novel bacterium that biologically generates silver nanoparticles (AgNPs). This bacterium, designated strain F202Z8T, was isolated from a rusty iron plate found in the intertidal region of Taean, South Korea. The morphological, biochemical and molecular characteristics predicted that strain F202Z8T belongs to the family Flavobacteriaceae. Phylogenetic analysis based on 16S rRNA gene sequence revealed that strain F202Z8T forms a distinct lineage with closely related genera Maribacter, Pelagihabitans, Pseudozobellia, Zobellia, Pricia, and Costertonia and showed the highest similarity to Maribacter aestuarii GY20T (94.5%). The digital DNA–DNA hybridization and average nucleotide identity values calculated from the whole genome-sequence comparison between strain F202Z8T and other members of the family Flavobacteriaceae were in the ranges of 12.7%–16.9% and 70.3%–74.4%, respectively, suggesting that strain F202Z8T represented a novel genus. The complete genome sequence of strain F202Z8T is 4,723,614 bp, with 43.26% G + C content. Based on the COG, GO, KEGG, NR, and Swiss-Prot databases, the genomic analysis of F202Z8T revealed the presence of 17 putative genes responsible for the synthesis of AgNPs. Our polyphasic taxonomic results suggested that this strain represents a novel species of a novel genus in the family Flavobacteriaceae, for which the name Aggregatimonas sangjinii gen. nov., sp. nov. is proposed. The type strain of Aggregatimonas sangjinii is F202Z8T (= KCCM 43411T = LMG 31494T). Overall, our data provide fundamental information to potentially utilize this novel bacterium for synthesis of nanoparticles. [ABSTRACT FROM AUTHOR]

Two novel strains, BT213T and BT327T, were isolated from the soil collected in Uijeongbu city, Korea. Cells of strains were Gram negative, aerobic, and non-motile. Phylogenetic analysis based on 16S rRNA gene sequences showed that strains BT213T and BT327T formed two distinct lineages within the family Hymenobacteraceae (order Cytophagales, class Cytophagia). Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain BT213T and BT327T belonged to the genus Pontibacter. Strain BT213T showed the highest similarities of 97.8% with Pontibacter deserti JC215T. Strain BT327T showed the highest sequence similarity of 96.5% with Pontibacter mucosus PB3T. Optimal growth occurred at 25 °C, pH 7, and in the absence of NaCl. The major cellular fatty acid of strains BT213T and BT327T were iso-C15:0 and summed feature 4 (iso-C17:1 I/anteiso-C17:1 B). Strains BT213T and BT327T had MK-7 as major respiratory quinone and phosphatidylethanolamine as major polar lipids. The genome size of strains BT213T and BT327T were 4,072,018 bp and 4,314,171 bp, respectively. The genomic G + C mol% of strains BT213T and BT327T are 45.6% and 46.1%, respectively. Based on biochemical, chemotaxonomic, and phylogenetic analysis, two novel species Pontibacter fetidus BT213T (KCTC 72345T = NBRC 114379T) and Pontibacter burrus BT327T (KCTC 72412T = NBRC 114376T) are proposed as type strains. [ABSTRACT FROM AUTHOR]

Nine non-pigmented, motile, Gram-negative bacteria originally designated as Alteromonas macleodii deep-sea ecotypes, were isolated from seawater samples collected from four separate locations; two deep-sea sites in the Mediterranean Sea and surface water of the Aegean Sea and English Channel. The six strains studied in vitro were found to tolerate up to 20 % NaCl. The DNA-DNA relatedness between the deep-sea ecotype strains was found to be between 75 and 89 %, whilst relatedness with the validly named Alteromonas species was found to be between 31 and 69 %. The average nucleotide identity (ANI) amongst the deep-sea ecotype strains was found to be 98-100 %; the in silico genome-to-genome distance (GGD), 85-100 %; the average amino acid identity (AAI) of all conserved protein-coding genes, 95-100 %; and the strains possessed 30-32 of the Karlin's genomic signature dissimilarity. The ANI between the deep-sea ecotype strains and A. macleodii ATCC 27126 and Alteromonas australica H 17 was found to be 80.6 and 74.6 %, respectively. A significant correlation was observed between the phenotypic data obtained in vitro and data retrieved in silico from whole genome sequences. The results of a phylogenetic study that incorporated a 16S rRNA gene sequence analysis, multilocus phylogenetic analysis (MLPA) and genomic analysis, together with the physiological, biochemical and chemotaxonomic data, clearly indicated that the group of deep-sea ecotype strains represents a distinct species within the genus Alteromonas. Based on these data, a new species, Alteromonas mediterranea, is proposed. The type strain is DE ( = CIP 110805 = LMG 28347 = DSM 17117). [ABSTRACT FROM AUTHOR]

Few diazotrophs have been found to belong to the family Cytophagaceae so far. In the present study, a Gram-negative, rod-shaped bacterium that forms red colonies, was isolated from sands of the Takalamakan desert. It was designated H4XT. Phylogenetic and biochemical analysis indicated that the isolate is a new species of the genus Pontibacter. The 16S rRNA gene of H4XT displays 94.2–96.8% sequence similarities to those of other strains in Pontibacter. The major respiratory quinone is menaquinone-7 (MK-7). The DNA G+C content is 46.6 mol%. The major cellular fatty acids are iso-C15∶0, C16∶1ω5c, summed feature 3 (containing C16∶1ω6c and/or C16∶1ω7c) and summed feature 4 (comprising anteiso-C17∶1B and/or iso-C17∶1I). The major polar lipids are phosphatidylethanolamine (PE), one aminophospholipid (APL) and some unknown phospholipids (PLs). It is interesting to see that this bacterium can grow very well in a nitrogen-free medium. PCR amplification suggested that the bacterium possesses at least one type of nitrogenase gene. Acetylene reduction assay showed that H4XT actually possesses nitrogen-fixing activity. Therefore, it can be concluded that H4XT is a new diazotroph. We thus referred it to as Pontibacter diazotrophicus sp. nov. The type strain is H4XT ( = CCTCC AB 2013049T = NRRL B-59974T). [ABSTRACT FROM AUTHOR]

A non-pigmented, motile, Gram-negative bacterium designated H 17 was isolated from a seawater sample collected in Port Phillip Bay (the Tasman Sea, Pacific Ocean). The new organism displayed optimal growth between 4 and 37 °C, was found to be neutrophilic and slightly halophilic, tolerating salt water environments up to 10 % NaCl. Strain H 17 was found to be able to degrade starch and Tween 80 but unable to degrade gelatin or agar. Phosphatidylglycerol (27.7 %) and phosphatidylethanolamine (72.3 %) were found to be the only associated phospholipids. The major fatty acids identified are typical for the genus Alteromonas and include C, Cω7, Cω8 and Cω7. The G+C content of the DNA was found to be 43.4 mol%. A phylogenetic study, based on the 16S rRNA gene sequence analysis and Multilocus Phylogenetic Analysis, clearly indicated that strain H 17 belongs to the genus Alteromonas. The DNA−DNA relatedness between strain H 17 and the validly named Alteromonas species was between 30.7 and 46.4 mol%. Based on these results, a new species, Alteromonas australica, is proposed. The type strain is H 17 (= KMM 6016 = CIP 109921). [ABSTRACT FROM AUTHOR]