Marinobacter iranensis sp. nov., a slightly halophilic bacterium from a hypersaline lake.

A novel halophilic bacterium, strain 71-iT, was isolated from Inche-Broun hypersaline lake in Golestan province, in the north of Iran. It was a Gram-stain-negative, non-endospore forming, rod-shaped bacterium. It grew at 4-40 °C (optimum 30 °C), pH 6.0-11.0 (optimum pH 7.5) and with 0.5-15 % (w/v) NaCl [optimum 3 % (w/v) NaCl]. The results of phylogenetic analyses based on the 16S rRNA gene sequence comparison indicated its affiliation to the genus Marinobacter and the low percentage of identity with the most closely related species (97.5 %), indicated its placement as a novel species within this genus. Digital DNA-DNA hybridization (dDDH) values and average nucleotide identity (ANI) analyses of this strain against closely related species confirmed its condition of novel taxon. On the other hand, the percentage of the average amino acid identity (AAI) affiliated strain 71-iT within the genus Marinobacter. The DNA G+C content of this isolate was 57.7 mol%. The major fatty acids were C16 : 0 and C16 : 1ω7c and/or C16 : 1 ω6c. Ubiquinone-9 was the major isoprenoid quinone and diphosphatidylglycerol (DPG), phosphatidylglycerol (PG) and phosphatidylethanolamine (PE) were the main polar lipids of this strain. On the basis of the phylogenomic and phenotypic (including chemotaxonomic) features, we propose strain 71-iT (= IBRC M 11023T = CECT 30160T = LMG 29252T) as the type strain of a novel species within the genus Marinobacter, with the name Marinobacter iranensis sp. nov. Genomic detections of this strain in various metagenomic databases indicate that it is a relatively abundant species in environments with low salinities (approximately 5 % salinity), but not in hypersaline habitats with high salt concentrations.

Halomonas lysinitropha sp. nov., a novel halophilic bacterium isolated from a hypersaline wetland.

We carried out a polyphasic taxonomic study on a new halophilic strain designated 3(2)T, isolated from Meighan wetland, Iran. Cells of the novel strain were Gram-stain-negative, non-hemolytic, catalase- and oxidase-positive, rod-shaped, non-endospore-forming and motile. Cell growth occurred at 3-15 % NaCl (w/v; optimum, 5 %), pH 7.0-9.0 (optimum, pH 7.5-8.0) and 15-35 °C (optimum, 30 °C). 16S rRNA gene sequence comparisons confirmed the affiliation of strain 3(2)T to the class Gammaproteobacteria and the genus Halomonas with highest similarity to Halomonas daqiaonensis YCSA28T (98.4 %) and Halomonas ventosae Al12T (97.9 %). Experimental and in silico DNA-DNA hybridization values were 42.7 and 35.1% with H. daqiaonensis IBRC-M 10931T and 48 and 35.2% with H. ventosae IBRC-M 10566T, respectively, and indicated that they are different members of the same genus. The genome of the type strain was characterized by a size of 3.83 Mbp with 63 scaffolds and a G+C content of 64.8 mol%. Moreover, the average nucleotide identity values against H. ventosae Al12T and H. daqiaonensis YCSA28T were 88.8 and 88.5 %, respectively. The predominant respiratory quinone was Q-9 (92 %) with Q-8 (8 %) as a minor component. Major fatty acids were C16 : 0 cyclo, C19 : 0 ω8c, C16 : 1 ω7c and/or iso-C15:0 2-OH, C12 : 0 3-OH and C18 : 1 ω7c. The polar lipid profile of the strain contained diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphoaminoglycolipid and four unidentified phospholipids. According to our results, strain 3(2)T could be classified as a novel species in the genus Halomonas for which the name Halomonas lysinitropha sp. nov. is proposed. The type strain is 3(2)T (=IBRC M 10929T=LMG 29450T=CIP 111708T).

Salipaludibacillus halalkaliphilus sp. nov., a moderately haloalkaliphilic bacterium from a coastal-marine wetland.

A Gram-stain-positive, endospore-forming rod-shaped non-motile, moderately halophilic and alkaliphilic bacterium, strain GASy1T, was isolated from a water sample from Gomishan, a marine wetland in Iran. GASy1T required at least 0.5 % (w/v) NaCl for growth and was able to grow at NaCl concentrations of up to 15 % (w/v), with optimum growth occurring at 5 % (w/v) NaCl. The optimum pH and temperature for growth were pH 8.5-9.0 and 30 °C, respectively, while it was able to grow over a pH range and a temperature range of 7.5-10.0 and 4-40 °C, respectively. GASy1T was catalase-positive and oxidase-negative. Analysis of 16S rRNA gene sequences revealed that GASy1T represents a member of the genus Salipaludibacillus, family Bacillaceae within the order Bacillales, showing 97.4 % sequence similarity to Salipaludibacillus neizhouensis JSM 071004T, and 96.2 and 95.7 % sequence similarity to Salipaludibacillus agaradhaerens AC 13T and Salipaludibacillus aurantiacus S9T, respectively. The DNA G+C content of GASy1T was 38.8 mol%. The polar lipids of the strain were phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine and two unidentified phospholipids and its major cellular fatty acids were anteiso-C15 : 0, C16 : 0 and iso-C15 : 0. The isoprenoid quinone was MK-7. DNA-DNA hybridization experiments revealed a low level of relatedness between GASy1T and Salipaludibacillus neizhouensis IBRC-M 10892T (18 %). On the basis of a combination of phenotypic, chemotaxonomic and phylogenetic features, GASy1T represents a novel species of the genus Salipaludibacillus, for which the name Salipaludibacillus halalkaliphilus sp. nov. is proposed. The type strain of Salipaludibacillus halalkaliphilus is GASy1T (=IBRC M 10902T=LMG 28385T).

Isolation, functional evaluation of probiotic properties and molecular identification of strains isolated from Iranian poultry's gut.

Background and Objectives: The use of probiotics as an alternative to antibiotics in poultry diets has attracted a lot of interest recently. In this context, the determination of probiotic characteristics was evaluated on several isolates obtained from Iranian poultry's gut. Materials and Methods: Probiotic characteristics such as hemolysis activity, acid, bile, gastric juice tolerate, in vitro adhesion assay, cell surface properties (hydrophobicity, auto-aggregation and co-aggregation) and antibiotic susceptibility test were evaluated. Finally, selected isolates identified molecularly after temperature-salt tolerance and extracellular enzyme activity (amylase, protease and cellulose). Results: Out of 362 strains isolated from native poultry in three geographical regions of Iran, nine strains (belong to Bacillus sp., Enterococcus sp., Pediococcus sp., Lactobacillus sp., Kluyveromyces sp.) showed resistance against gastrointestinal physiological conditions, desirable surface properties, ability to adhere to epithelial intestine cell line and antibiotic susceptibility. Also, these strains were discovered to be temperature-salt tolerant but, only a small number of them were able to produce hydrolase enzymes. Conclusion: According to the results, the selected strains can be introduced as native probiotic candidates for utilization in novel poultry feeds.