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New Microbes and New Infections May 2017We report the main characteristics of P3515 sp. nov., P3516 sp. nov., P2481 sp. nov., P3554 sp. nov., P3089 sp. nov., P3587 sp. nov., P3532 sp. nov., P3469 sp....
Description of sp. nov., sp. nov., sp. nov., sp. nov., sp. nov., sp. nov., sp. nov., sp. nov. and sp. nov., nine halophilic new species isolated from human stool.
We report the main characteristics of P3515 sp. nov., P3516 sp. nov., P2481 sp. nov., P3554 sp. nov., P3089 sp. nov., P3587 sp. nov., P3532 sp. nov., P3469 sp. nov. and P3610 sp. nov., that were isolated in 2016 from salty stool samples (≥1.7% NaCl) from healthy Senegalese living at Dielmo and N'diop, two villages in Senegal.
PubMed: 28280541
DOI: 10.1016/j.nmni.2017.01.010 -
Biotechnology Reports (Amsterdam,... Dec 2015A marine ascidian-associated bacterium, RSK CAS9, was optimized for lipase production by response surface methodology using marine waste as substrate. The central...
A marine ascidian-associated bacterium, RSK CAS9, was optimized for lipase production by response surface methodology using marine waste as substrate. The central composite design was employed, and the optimal medium constituents for maximum lipase production (1355.81 U/ml) were determined to be tuna powder (14.58 g/l), olive oil (5.05 ml/l); NaCl (72.42 g/l), temperature (45 °C) and pH 9.0. An alkaline lipase was purified to 8.46 fold with 1193.59 U mg specific activities with the molecular weight of 44 kDa. The activity was substantially inhibited by EDTA and PMSF, indicating that it was a metalloenzyme serine residue which was essential for catalytic activity. Thus, lipase production by microbial conversion of marine fish wastes in this study suggested its potential utilization for the production of high value products.
PubMed: 28352574
DOI: 10.1016/j.btre.2015.09.002 -
Scientific Reports Apr 2017In this study, genomic DNA was screened from Halobacillus andaensis NEAU-ST10-40 by selection in Escherichia coli KNabc lacking three major Na/H antiporters. One gene...
In this study, genomic DNA was screened from Halobacillus andaensis NEAU-ST10-40 by selection in Escherichia coli KNabc lacking three major Na/H antiporters. One gene designated upf0118 exhibiting Na(Li)/H antiport activity was finally cloned. Protein alignment showed that UPF0118 shares the highest identity of 81.5% with an unannotated gene encoding a protein with uncharacterized protein function belonging to UPF0118 family from H. kuroshimensis, but shares no identity with all known specific Na(Li)/H antiporter genes or genes with Na(Li)/H antiport activity. Growth test, western blot and Na(Li)/H antiport assay revealed that UPF0118 as a transmembrane protein exhibits pH-dependent Na(Li)/H antiport activity. Phylogenetic analysis indicated that UPF0118 clustered with all its homologs belonging to UPF0118 family at a wide range of 22-82% identities with the bootstrap value of 92%, which was significantly distant with all known specific single-gene Na(Li)/H antiporters and single-gene proteins with the Na(Li)/H antiport activity. Taken together, we propose that UPF0118 should represent a novel class of Na(Li)/H antiporter. To the best of our knowledge, this is the first report on the functional analysis of a protein with uncharacterized protein function as a representative of UPF0118 family containing the domain of unknown function, DUF20.
Topics: Amino Acid Sequence; Antiporters; Bacterial Proteins; Base Sequence; Cloning, Molecular; Halobacillus; Hydrogen-Ion Concentration; Ion Transport; Lithium; Membrane Proteins; Phylogeny; Sequence Analysis, DNA; Sequence Homology, Amino Acid; Sodium; Sodium-Hydrogen Exchangers
PubMed: 28374790
DOI: 10.1038/srep45936 -
Journal, Genetic Engineering &... Oct 2020Halophiles offer an attractive source of genes conferring salt tolerance. Halobacillus trueperi SS1 strain of Lunsu, Himachal Pradesh, India, a strict halophile, was...
BACKGROUND
Halophiles offer an attractive source of genes conferring salt tolerance. Halobacillus trueperi SS1 strain of Lunsu, Himachal Pradesh, India, a strict halophile, was exploited to isolate and clone the genes for salt tolerance. The genomic library of BamH1 digest of H. trueperi SS1 was constructed in pUC19, and recombinants were screened for salt tolerance on an LB medium containing ampicillin (100 μg/ml) and NaCl (0 to 1.5 M).
RESULTS
One recombinant clone named as salt-tolerant clone (STC) conferred salt tolerance to host Escherichia coli/DH5α, which showed growth in the LB medium supplemented with ampicillin and 1.2 M NaCl. Restriction digestion and PCR analysis revealed the presence of an insert of approximately 2000 bp in the STC. DNA sequencing of the 2-kb insert on both strands yielded a sequence of 2301 nucleotides. Protein BLAST analysis of 2301-bp sequence of H. trueperi SS1 present in STC showed 97% identity to multidrug transport ATP binding/permease protein of Halobacillus karajensis. The insert contained in STC was subcloned into pGEX4T2 vector, and the recombinant clone STC/pGEX4T2 conferred salt tolerance to the bacterial host E. coli.
CONCLUSIONS
The present study led to the isolation of salt tolerance gene encoding a putative multidrug transport ATP binding/permease protein from H. trueperi SS1. The salt tolerance gene can be subcloned for transferring salt tolerance traits into agricultural crop plants for cultivation in saline and coastal lands.
PubMed: 33025336
DOI: 10.1186/s43141-020-00070-6 -
SpringerPlus 2015Five halophilic bacterial isolates namely SS1, SS2, SS3, SS5 and SS8 were isolated from soil sediments of Lunsu, a salty water body. All the bacterial isolates showed...
Five halophilic bacterial isolates namely SS1, SS2, SS3, SS5 and SS8 were isolated from soil sediments of Lunsu, a salty water body. All the bacterial isolates showed growth in LB medium containing up to 8.7% NaCl, pH 7-8 and at temperature range of 30-37°C. The bacterial isolates SS1 and SS3 require at least 3.8% NaCl for their growth, indicating their strict halophilic nature. Interestingly, bacterial isolates SS2, SS5 and SS8 but not SS1 and SS3 exhibited growth in medium supplemented with KCl. Accordingly, Na(+) and K(+) ions were detected at 1.39 and 0.0035%, respectively in Lunsu water. All the bacterial isolates were analyzed by random amplification of polymorphic DNA (RAPD) using four different random primers and produced PCR fragments ranging from 0.1 to 5 kb in size. Phylogenetic tree based on RAPD finger prints showed that SS1 and SS3 formed one group, while SS2 and SS5 formed the second group, whereas SS8 was out group. Sequence analysis of 16S rDNA identified SS1 and SS3 as Halobacillus trueperi, SS2 as Shewanella algae, SS5 as Halomonas venusta, and SS8 as Marinomonas sp. were deposited in GenBank with accession numbers of KM260166, KF751761, KF751760, KF751762 and KF751763, respectively. This is the first report on the presence of diverse halophilic bacteria in the foot hills of Himalayas.
PubMed: 26090321
DOI: 10.1186/s40064-015-1028-1 -
Marine Drugs Jul 2019Quorum sensing (QS) antagonists have been proposed as novel therapeutic agents to combat bacterial infections. We previously reported that the secondary metabolite...
Quorum sensing (QS) antagonists have been proposed as novel therapeutic agents to combat bacterial infections. We previously reported that the secondary metabolite 3-methyl--(2'-phenylethyl)-butyramide, produced by a marine bacterium identified as , inhibits QS controlled phenotypes in multiple Gram-negative reporter strains. Here we report that -phenethyl hexanamide, a structurally-related compound produced by the marine bacterium , similarly demonstrates QS inhibitory properties. To more fully explore structure-activity relationships within this new class of QS inhibitors, a panel of twenty analogs was synthesized and biologically evaluated. Several compounds were identified with increased attenuation of QS-regulated phenotypes, most notably -(4-fluorophenyl)-3-phenylpropanamide against the marine pathogen (IC = 1.1 µM). These findings support the opportunity to further develop substituted phenethylamides as QS inhibitors.
Topics: Amides; Anti-Bacterial Agents; Halobacillus; Inhibitory Concentration 50; Quorum Sensing; Secondary Metabolism; Structure-Activity Relationship; Vibrio
PubMed: 31266202
DOI: 10.3390/md17070389 -
BMC Microbiology Oct 2015Biosurfactants are surface-active biomolecules with great applicability in the food, pharmaceutical and oil industries. Endospore-forming bacteria, which survive for...
BACKGROUND
Biosurfactants are surface-active biomolecules with great applicability in the food, pharmaceutical and oil industries. Endospore-forming bacteria, which survive for long periods in harsh environments, are described as biosurfactant producers. Although the ubiquity of endospore-forming bacteria in saline and hypersaline environments is well known, studies on the diversity of the endospore-forming and biosurfactant-producing bacterial genera/species in these habitats are underrepresented.
METHODS
In this study, the structure of endospore-forming bacterial communities in sediment/mud samples from Vermelha Lagoon, Massambaba, Dois Rios and Abraão Beaches (saline environments), as well as the Praia Seca salterns (hypersaline environments) was determined via denaturing gradient gel electrophoresis. Bacterial strains were isolated from these environmental samples and further identified using 16S rRNA gene sequencing. Strains presenting emulsification values higher than 30 % were grouped via BOX-PCR, and the culture supernatants of representative strains were subjected to high temperatures and to the presence of up to 20 % NaCl to test their emulsifying activities in these extreme conditions. Mass spectrometry analysis was used to demonstrate the presence of surfactin.
RESULTS
A diverse endospore-forming bacterial community was observed in all environments. The 110 bacterial strains isolated from these environmental samples were molecularly identified as belonging to the genera Bacillus, Thalassobacillus, Halobacillus, Paenibacillus, Fictibacillus and Paenisporosarcina. Fifty-two strains showed emulsification values of at least 30%, and they were grouped into 18 BOX groups. The stability of the emulsification values varied when the culture supernatants of representative strains were subjected to high temperatures and to the presence of up to 20% NaCl. The presence of surfactin was demonstrated in one of the most promising strains.
CONCLUSION
The environments studied can harbor endospore-forming bacteria capable of producing biosurfactants with biotechnological applications. Various endospore-forming bacterial genera/species are presented for the first time as biosurfactant producers.
Topics: Bacteria, Aerobic; Brazil; Cluster Analysis; DNA, Bacterial; DNA, Ribosomal; Endospore-Forming Bacteria; Environmental Microbiology; Mass Spectrometry; Molecular Sequence Data; Phylogeny; RNA, Ribosomal, 16S; Sequence Analysis, DNA; Sodium Chloride; Surface-Active Agents
PubMed: 26511622
DOI: 10.1186/s12866-015-0575-5 -
Genome Announcements Jun 2016Halobacillus sp. strain KGW1 is a moderately halophilic, rod shaped, Gram-positive, yellow pigmented, alkaline protease-producing bacterium isolated from a water sample...
Draft Genome Sequence of Halobacillus sp. Strain KGW1, a Moderately Halophilic and Alkaline Protease-Producing Bacterium Isolated from the Rhizospheric Region of Phragmites karka from Chilika Lake, Odisha, India.
Halobacillus sp. strain KGW1 is a moderately halophilic, rod shaped, Gram-positive, yellow pigmented, alkaline protease-producing bacterium isolated from a water sample from Chilika Lake, Odisha, India. Sequencing of bacterial DNA assembled a 3.68-Mb draft genome. The genome annotation analysis showed various gene clusters for tolerance to stress, such as elevated pH, salt concentration, and toxic metals.
PubMed: 27365341
DOI: 10.1128/genomeA.00361-16