Agaribacter marinus gen. nov., sp. nov., an agar-degrading bacterium from surface seawater

Ningiella ruwaisensis gen. nov., sp. nov., a member of the family Alteromonadaceae isolated from marine water of the Arabian Gulf

Strain B66^T was isolated from a marine water sample collected at Al Ruwais, located on the northern tip of Qatar. Cells were Gram-stain-negative, strictly aerobic and short- rod-shaped with a polar flagellum. The isolate was able to grow at 15-45 °C (optimum, 30 °C), at pH 5-11 (optimum, pH 6.5-8) and with 0-6 % NaCl. 16S rRNA gene sequence analysis revealed that strain B66^T was affiliated with the family Alteromonadaceae, sharing the highest sequence similarities to the genera Alteromonas (93.7-95.4 %), Aestuariibacter (94.0-95.1 %), Agaribacter (93.3-93.7 %), Glaciecola (92.0-93.7 %), Marisendiminitalea (93.2-93.3 %) and Planctobacterium (92.9 %). In the phylogenetic trees, strain B66^T demonstrated the novel organism formed a distinct lineage closely associated with Aestuariibacter and Planctobacterium. Major fatty acids were C_16 : 0, summed feature 3 (C_16 : 1  ω7c/C_16 : 1  ω6c/iso-C_15 : 0 2-OH and iso-C_15 : 0 3-OH. The major respiratory quinone was ubiquinone-8 and the major polar lipids are phosphatidylglycerol and phosphatidylethanolamine. The DNA G+C content derived from the genome was 43.2 mol%. Based on the phenotypic, chemotaxonomic, phylogenetic and genomic data, strain B66^T is considered to represent a novel species and genus for which the name Ningiella ruwaisensis gen. nov., sp. nov., is proposed. The type strain is B66^T (=QCC B003/17^T=LMG 30288 ^T=CCUG 70703^T).

Exoenzyme-producing halophilic bacteria from the former Lake Texcoco: identification and production of n-butyl oleate and bioactive peptides

Halophilic bacterias from saline soil from former Lake Texcoco were isolated, identified based on 16 rRNA and tested to produce glucolytic, nucleolytic, proteolytic and lipolytic exoenzymes. The Bacillus, Virgibacillus, Kocuria, Salinicoccus, Gracilibacillus, Halobacillus, Tenuibacillus and Nesterekonia genera where identified. Lipase/eserases and proteases from Nesterenkonia sp. and Nesterenkonia aethiopica showed halotolerant characteristics and were selected to synthesize the oleochemical n-butyl oleate and antioxidant peptides from muscle protein of common carp (Cyprinus carpio), respectively. In organic media (2,2,4-Trimethylpentane), the lipase/esterases from Nesterenkonia sp. (0.6 U/mL) and N. aethiopica (1.2 U/mL) achieved a 62.7% and 53.2% of n-butyl oleate conversion, respectively. The protein hydrolysis from muscle of common carp (C. carpio) showed a degree of hydrolysis of 4.5 ± 0.2% and 2.8 ± 0.1% when proteases from Nesterenkonia sp. and N. aethiopica were used, respectively. Three peptidic fractions ranging molecular masses between 254 and 1002 Da [M + H] show antioxidant scavenging activity, and the principal fraction with a peptide of 547.3 Da [M + H] showed an inhibition of 37.7 ± 1.8% and 16.3 ± 0.6%, when 2,2-diphenyl-1-picrylhydrazyl and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) were used, respectively. These findings showed that the enzymatic battery of the halophilic bacteria from former lake Texcoco can be used in hydrolysis and synthesis of molecules with applications in different fields as food technology or bioenergy.

Marisediminitalea mangrovi gen. nov., sp. nov., isolated from marine mangrove sediment, and reclassification of Aestuariibacter aggregatus as Marisediminitalea aggregata comb. nov

Strain GS-14^T was isolated from a mangrove sediment sample collected at Beilun Estuary National Nature Reserve, Guangxi Province, PR China. Cells were Gram-stain-negative, strictly aerobic and rod-shaped with a polar flagellum. Optimal growth occurred in the presence of 3-6 % (w/v) NaCl, at pH 6-8 and at a temperature of 37 °C. The predominant polar lipids were phosphatidylglycerol and phosphatidylethanolamine. Ubiquinone 8 (Q-8) was the sole respiratory quinone. The major fatty acids (>10 % of the total fatty acids) were summed feature 3 (C_16 : 1ω7c and/or C_16 : 1ω6c) and C_16 : 0. The DNA G+C content was 47.6 mol%. Phylogenetic analysis based on the 16S rRNA gene sequence indicated that strain GS-14^T had the highest sequence similarity to Aestuariibacter aggregatus WH169^T (96.63 %), Aliiglaciecola coringensis AK49^T (96.56 %) and Alteromonas lipolytica JW12^T (96.22 %). In addition, the OrthoANIu value and dDDH values calculated from the genomes of strain GS-14^T and A. aggregatus WH169^T were 79.5 and 21.9 %, respectively. Based on the polyphasic taxonomic results, strain GS-14^T is considered to represent a novel species in a new genus, for which the name Marisediminitalea mangrovi gen. nov., sp. nov. is proposed. The type strain of Marisediminitalea mangrovi is GS-14^T (=KCTC 72401^T=MCCC 1K03622^T). Because Aestuariibacter aggregatus WH169^T clustered with strain GS-14^T in the phylogenetic trees and was clearly separated from the two species within the genus Aestuariibacter, it is reclassified as a member of the genus Marisediminitalea as Marisediminitalea aggregata comb. nov. (type strain WH169^T=CGMCC 1.8995^T=LMG 25283^T). The type species of the genus Marisediminitalea is Marisediminitalea aggregata gen. nov., comb. nov.

Hydrocarboniclastica marina gen. nov., sp. nov., a marine hydrocarbonoclastic bacterium isolated from an in situ enriched hydrocarbon-degrading consortium in sea sediment

A Gram-stain-negative, motile, non-spore-forming, aerobic and rod-shaped bacterial strain, Soil36-7^T, was isolated from an in situ enriched hydrocarbon-degrading consortium in South China Sea sediment. Strain Soil36-7^T grew at 4-40 °C (optimum 28-32 °C), at pH 5-10 (pH 7-8) and in the presence of 1-12 % (w/v) NaCl (3-6 %). Phylogenetic analyses based on 16S rRNA gene sequences and a genome-based approach using UBCGs (up-to-date bacterial core genes) showed Soil36-7^T formed a distinct branching lineage within the family Alteromonadaceae. 16S rRNA gene sequence similarity was 92.9, 92.1 and >88.3 % between strain Soil36-7^T and the type species of the genera Marinobacter, Tamilnaduibacter and the other genera of the family Alteromonadaceae, respectively. The major fatty acids in Soil36-7^T were C16 : 0, C16 : 1ω6/7c, C16 : 0 10-methyl, C18 : 1ω7c, C12 : 0 and C18 : 0. The predominant respiratory quinone was Q-9, with a minor amount of Q-10 (3.5 %). The major polar lipids were phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol, and various unidentified glycolipids, phospholipids, aminophospholipids and other polar lipids. The DNA G+C content was 57.9 mol%. On the basis of phylogenetic, genomic, phenotypic and chemotaxanomic characteristics, strain Soil36-7^T could be classified as representing a novel species of a new genus within the family Alteromonadaceae, for which the name Hydrocarboniclastica marina gen. nov., sp. nov. is proposed. The type strain of the type species is Soil36-7^T (=MCCC 1A12105^T=KCTC 62334^T).

Neptunicella marina gen. nov., sp. nov., isolated from surface seawater

A Gram-stain-negative, aerobic, short rod-shaped bacterium with a single polar flagellum, designated strain S27-2^T, was isolated from surface seawater from the Indian Ocean. Growth was observed in 0-12.0 % (w/v) NaCl with an optimum of 0.5-2.0 % (w/v) NaCl, pH 6.0-9.0 with an optimum of pH 7.0, and growth temperature of 10-41 °C with an optimum of 25-37 °C. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain S27-2^T belonged to the family Alteromonadaceae and formed a distinct lineage with the type strain of Pseudobowmanella zhangzhouensis. Levels of 16S rRNA gene sequence similarity between strain S27-2^T and members of related genera included in the trees ranged from 86.7 to 93.8 %. Strain S27-2^T contained Q-8 as the predominant ubiquinone. The principal fatty acids (>10 %) were C16 : 0 (22.1 %), C16 : 1ω7c/ω6c (22.7 %) and C18 : 1ω7c/ω6c (20.1 %). The polar lipids consisted of diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, one unidentified phospholipid and two unknown lipids. The G+C content of strain S27-2^T was 43.7 mol%. On the basis of the polyphasic taxonomic evidence presented in this study, strain S27-2^T should be classified as a novel species in a new genus within the family Alteromonadaceae, for which the name Neptunicella marina gen. nov., sp. nov. is proposed, with the type strain S27-2^T (= KCTC52335^T=MCCC 1A02149^T).