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International Microbiology : the... May 2023Ectoine and hydroxyectoine are compatible solutes with enormous potential for use in the medical and cosmetic industries. Considering the excellent osmoprotective...
Ectoine and hydroxyectoine are compatible solutes with enormous potential for use in the medical and cosmetic industries. Considering the excellent osmoprotective properties of these compatible solutes, we investigate the presence of four compatible solutes (ectoine, hydroxyectoine, proline, and glutamic acid) quantitatively by liquid chromatography-tandem mass spectrometry (LC-MS/MS) in forty-five halophilic/halotolerant bacterial isolates. We determined ectoine production by Marinibacillus sp., Nesterenkonia xinjiangensis, Halobacillus sp., Bacillus patagoniensis, Virgibacillus picturae, Halomonas neptunia, Bacillus patagoniensis, Gracilibacillus sp., Thalassobacillus devorans, Microbacterium sp., Nesterenkonia sp., and Bacillus agaradhaerens, and this production was NaCl dependent. Additionally, the production of hydroxyectoine was observed in six bacterial isolates (Nesterenkonia xinjiangensis, Halobacillus sp., Halomonas neptunia, Thalassobacillus devorans, Nesterenkonia sp., and Bacillus agaradhaerens) which was NaCl and temperature dependent. The study identified new bacterial isolates producing ectoine or hydroxyectoine. While the ectoine production in many different Bacillus members and a few Nesterenkonia have been documented before, ectoine production by Bacillus patagoniensis and Nesterenkonia xinjiangensis has not been shown so far. Further, ectoine production by a member of the genus Thalassobacillus (Thalassobacillus devorans) was demonstrated experimentally for the first time. The findings reported in the study may serve as a basis for the large-scale production of ectoine and hydroxyectoine in the future.
Topics: Sodium Chloride; Chromatography, Liquid; Tandem Mass Spectrometry
PubMed: 36342583
DOI: 10.1007/s10123-022-00289-y -
Journal of Basic Microbiology Dec 2022Exopolymeric substances (EPS) produced by bacterial cells play a crucial role in the interaction of the cells with the surrounding environment. Halobacillus trueperi...
Exopolymeric substances (EPS) produced by bacterial cells play a crucial role in the interaction of the cells with the surrounding environment. Halobacillus trueperi manxer mangrove-16, an adhered bacterial isolate from the mangrove ecosystem was found to produce EPS that was observed by Alcian blue staining and congo red-coomassie blue agar. The EPS of the bacterial isolate exhibited emulsifying properties. Purification of the EPS by dialysis showed an emulsification index of 80% with hexadecane. Qualitative analysis and Fourier's Infrared spectroscopy (FTIR) revealed that the EPS was a glycoprotein in nature. The EPS showed no surface-active properties. Further exploration of the potential of the EPS interaction with metal solutions showed the ability of the bioemulsifier to cause precipitation in the metal solutions and particularly change the color of the Chromium (VI) solution. The scanning electron microscopy-energy-dispersive X-ray spectroscopy (SEM-EDS) of the cells and EPS particularly indicated the interaction of the EPS with the (Fe ) zerovalent iron nanoparticles and its effect on the cells and EPS of the bacteria. It is therefore concluded that the EPS is a crucial component that anchors the bacteria to particulate matter in the mangrove ecosystem and also plays an important role in interaction with metals and hydrocarbons.
Topics: Ecosystem; Halobacillus; Extracellular Polymeric Substance Matrix; Bacteria; Metals
PubMed: 36261394
DOI: 10.1002/jobm.202200352 -
Current Microbiology Oct 2022Fusarium wilt caused by Fusarium oxysporum f. sp. niveum is an important manifestation of continuous cropping barrier, which causes the quality and yield of watermelon...
Bama Pig Manure Organic Fertilizer Regulates the Watermelon Rhizosphere Bacterial Community to Inhibit the Occurrence of Fusarium Wilt Under Continuous Cropping Conditions.
Fusarium wilt caused by Fusarium oxysporum f. sp. niveum is an important manifestation of continuous cropping barrier, which causes the quality and yield of watermelon to decline. In early stage of this study, the organic fertilizer fermented by Bama pig manure applied in soil was proved to significantly inhibit the occurrence of disease by improving the structure of soil microbial community. However, the mechanism was not clear. The high-throughput sequencing technology, combined with network and PICRUSt2 function analysis was used to investigate it. MiSeq sequencing showed that the bacterial community of organic fertilizer treated soil was composed of 34 phyla and 768 genera, the number of genera was higher than that of sterile water treated soil. Fertilization significantly increased the diversity and changed the composition of bacterial community based on alpha, beta diversity, and ANOSIM/Adonis analysis. LEfSe species difference and network analysis showed that fertilization improved the relative abundance of bacteria with biological control or plant growth promotion characteristics in soil, such as Sphingomonas, Halobacillus, Nocardioides, and enhanced the interaction between rhizosphere bacteria, made the network structure more complex. PICRUSt2 also revealed fertilization promoted the bacterial function, such as metabolism and genetic information processing. These results showed that the pig manure organic fertilizer might reduce the occurrence of Fusarium wilt by regulating bacterial community, interaction, and functional metabolism in watermelon rhizosphere soil.
Topics: Animals; Bacteria; Citrullus; Fertilizers; Fusarium; Manure; Plant Diseases; Rhizosphere; Soil; Soil Microbiology; Swine; Water
PubMed: 36253496
DOI: 10.1007/s00284-022-03056-4 -
World Journal of Microbiology &... Sep 2022Traditionally fermented foods and beverages are still produced and consumed at a large scale in Romania. They are rich sources for novel lactic acid bacteria with...
Traditionally fermented foods and beverages are still produced and consumed at a large scale in Romania. They are rich sources for novel lactic acid bacteria with functional properties and with potential application in food industry or health. Lactobacillus helveticus 34.9, isolated from a home-made fermented milk is able to inhibit the growth of other bacteria, such as other lactic acid bacteria, but also strains of Bacillus subtilis, Bacillus cereus, Staphylococcus aureus, and Halobacillus hunanensis, a halobacterium isolated from the degraded wall of a Romanian monastery. L. helveticus 34.9 produces a large bacteriocin (35 KDa), active in a wide pH range, but inactivated by heat and proteinase K treatment. It shares about 20% sequence coverage with helveticin J, as determined by LC-MS analysis. Bacteriocin production was enhanced under stress conditions, especially when combined stresses were applied. Its mode of action and degree of inhibition depended on the concentration and on the indicator strain that was used; L. delbrueckii subsp. bulgaricus LMG 6901 cells from a suspension were killed, but the viability of H. hunanensis 5Hum cells was only reduced to 60%, within 8 h. However, the bacteriocin was able to prevent the bacterial growth of both indicator strains when added to the cultivation medium prior inoculation. Scanning electron microscopy images revealed morphological changes induced by the bacteriocin treatment in both sensitive strains, but more severe in the case of L. delbrueckii subsp. bulgaricus. Due to the broad antibacterial spectrum and its production under various stress conditions, the bacteriocin or the producing strain may find application in health, food and non-food related fields, including in the restoration of historical buildings.
Topics: Bacteria; Bacteriocins; Lactobacillus helveticus
PubMed: 36083397
DOI: 10.1007/s11274-022-03408-z -
Analytical Chemistry Sep 2022Fatty acids are a well-established class of compounds targeted as biosignatures for future missions to look for evidence of life on ocean worlds such as Europa and...
Fatty acids are a well-established class of compounds targeted as biosignatures for future missions to look for evidence of life on ocean worlds such as Europa and Enceladus. In order to establish their abiotic or biotic origin, we need to separate and quantify fatty acids to determine their relative abundances within a sample. In this study, we demonstrate the high potential of capillary electrophoresis coupled to mass spectrometry (CE-MS) for the efficient separation and sensitive detection of a wide variety of fatty acids. Three derivatization strategies were evaluated to allow the detection of fatty acids by positive ionization mode MS. Furthermore, CE-MS conditions were optimized to provide maximum separation efficiencies and detection sensitivities for the analysis of saturated and unsaturated fatty acids with even- and odd-numbered carbon chain lengths. Optimum separation and detection were obtained using a background electrolyte of 2 M acetic acid in 45% acetonitrile, after derivatization of the fatty acids with 2-picolylamine or ,-diethylethylenediamine. The limits of detection for the derivatized fatty acids using the optimized method ranged from 25 to 250 nM. The optimized method was also used for the analysis of fatty acids in cell cultures and natural samples. Two distinctive biosignatures were obtained for the microorganisms and . In addition, multiple fatty acids were detected in a natural sample from Mono Lake, California.
Topics: Acetates; Acetonitriles; Carbon; Electrolytes; Electrophoresis, Capillary; Fatty Acids; Mass Spectrometry
PubMed: 36066097
DOI: 10.1021/acs.analchem.2c02716 -
Journal of Applied Microbiology Nov 2022This study examined and characterized the extract for metabolites of Halobacillus marinus HMALI004 to understand their antibacterial activities against opportunistic...
AIMS
This study examined and characterized the extract for metabolites of Halobacillus marinus HMALI004 to understand their antibacterial activities against opportunistic marine pathogens, that is, Vibrio parahaemolyticus and Vibrio cholerae.
METHODS AND RESULTS
The bacterial strain HMALI004 was characterized as H. marinus, and an antibacterial spectral test revealed its inhibition against two opportunistic marine pathogens (V. parahaemolyticus and V. cholera). Fermentation broth of strain HMALI004 was subjected to column chromatography and high-performance liquid chromatography to separate antibacterial substances. Two compounds were successfully isolated and identified as 1H-pyrrole-2-carboxylic acid and 4-chloro-1H-pyrrole-2-carboxylic acid by mass spectrometry (MS) and nuclear magnetic resonance. The minimal inhibition concentration (MIC) values of 1H-pyrrole-2-carboxylic acid and 4-chloro-1H-pyrrole-2-carboxylic acid for V. parahaemolyticus were 25 μg/ml, while their MIC values for V. cholerae were 50 and 100 μg/ml, respectively. The reactive oxygen species (ROS) production of two pathogen strains treated with 1H-pyrrole-2-carboxylic acid and 4-chloro-1H-pyrrole-2-carboxylic acid were detected to investigate the antimicrobial mechanism. The results suggested that 4-chloro-1H-pyrrole-2-carboxylic acid exerted enhanced ROS production in V. parahaemolyticus, whereas 1H-pyrrole-2-carboxylic acid had a weaker effect. Both compounds caused a significant rise in ROS production in V. cholerae, causing severe damage to the cell wall and cytoplasm, leading to cell death.
CONCLUSIONS
The bacterium H. marinus HMALI004 was isolated from a shrimp pond and was found to produce antimicrobial compounds, which could inhibit the growth of opportunistic marine pathogens V. parahaemolyticus and V. cholerae by increasing ROS.
SIGNIFICANCE AND IMPACT OF THE STUDY
Successfully isolated antibacterial-producing strain, H. marinus HMALI004, and its antimicrobial compounds could be used as biological control agents for marine pathogens.
Topics: Halobacillus; Reactive Oxygen Species; Biological Control Agents; Bacteria; Vibrio parahaemolyticus; Vibrio cholerae; Anti-Bacterial Agents; Anti-Infective Agents; Plant Extracts
PubMed: 35929370
DOI: 10.1111/jam.15764 -
Folia Microbiologica Feb 2023Halotolerant bacteria get adapted to a saline environment through modified physiological/structural characteristics and may provide stress tolerance along with enhanced...
Halotolerant bacteria get adapted to a saline environment through modified physiological/structural characteristics and may provide stress tolerance along with enhanced growth to the host plants by different direct and indirect mechanisms. This study reports on multiple halotolerant plant growth-promoting rhizobacteria isolated from the coastal soils in Bangladesh, in fields where the halophytic wild rice Oryza coarctata is endemic. The aim was to find halotolerant bacteria for potential use as biofertilizer under normal/salt-stressed conditions. In this study, eight different strains were selected from a total of 20 rhizobacterial isolates from the saline-prone regions of Debhata and Satkhira based on their higher salt tolerance. 16S rRNA gene sequencing results of the rhizobacterial strains revealed that they belonged to Halobacillus, Bacillus, Acinetobactor, and Enterobactor genera. A total of ten halotolerant rhizobacteria (the other 2 bacteria were previously isolated and already reported as beneficial for rice growth) were used as both single inoculants and in combinations and applied to rice growing in pots. To investigate their capability to improve rice growth, physiological parameters such as shoot and root length and weight, chlorophyll content at the seedling stage as well as survival and yield at the reproductive stage were measured in the absence or presence (in concentration 40 or 80 mmol/L) of NaCl and in the absence or presence of the rhizobacteria. At the reproductive stage, only 50% of the uninoculated plants survived without setting any grains in 80 mmol/L NaCl in contrast to 100% survival of the rice plants inoculated with a combination of the rhizobacteria. The combined halotolerant rhizobacterial inoculations showed significantly higher chlorophyll retention as well as yield under the maximum NaCl concentration applied compared to application of single species. Thus, the use of a combination of halotolerant rhizobacteria as bioinoculants for rice plants under moderate salinity can synergistically alleviate the effects of stress and promote rice growth and yield.
Topics: Oryza; RNA, Ribosomal, 16S; Sodium Chloride; Salt Stress; Bacteria; Chlorophyll; Plant Roots; Soil Microbiology
PubMed: 35913659
DOI: 10.1007/s12223-022-00997-y -
Journal of Pharmaceutical and... May 2022The realistic implementation of electrochemistry into bacterial biosynthesis monitoring programs has always been a challenging task. In this study, two simple, rapid,...
The realistic implementation of electrochemistry into bacterial biosynthesis monitoring programs has always been a challenging task. In this study, two simple, rapid, selective, and sensitive potentiometric sensors were developed and optimized for quantitative analysis of the extremolyte / osmoprotector ectoine (ECT) in halophilic bacterial cultures and also in its related pharmaceutical products. The developed sensors were a Polyvinyl chloride membrane sensor (ECT-PVC) and a coated graphite sensor (ECT-CG). They were established based on the ion association complex of ectoine cation with phosphotungstic acid (ECT-PTA) counter anion as ion exchange site using dioctyl-phthalate (DOP) as a solvent mediator or plasticizer. The sensors exhibited fast, stable, selective, and linear Nernstian responses over a broad range of concentrations ranging from 1 × 10 to 1 × 10 M of the studied drug. The developed sensors were optimized and cross-validated with a proposed HPLC method according to ICH guidelines. The proposed methods were successfully employed to quantify the studied drug in three different types of halophilic bacterial cultures and in an ectoine nasal spray pharmaceutical product. The selected bacteria species were Chromohalobacter salexigens, Halobacillus halophilus, and Halomonas elongata. The proposed methods were statistically compared with the reported methods, demonstrating no significant difference with respect to accuracy and precision. Greenness and environmental impact were also evaluated for the proposed procedures, verifying that they were excellent green and eco-friendly analytical methods.
Topics: Amino Acids, Diamino; Pharmaceutical Preparations; Polyvinyl Chloride; Potentiometry
PubMed: 35217260
DOI: 10.1016/j.jpba.2022.114680 -
Bioengineered Feb 2022This study investigated the inhibitory activity of S61 and its active extract on potato dry rot pathogens and aimed at contributing to biocontrol agent development...
This study investigated the inhibitory activity of S61 and its active extract on potato dry rot pathogens and aimed at contributing to biocontrol agent development during potato storage. Three kinds of pathogens were isolated as target pathogenic fungi from dry rot tubers and determined as (Qing 9A-2), (Qing 9A-5-8) and (Qing 9A-1-1) by morphological and molecular identification. The strain S61 and its extract exhibited a higher inhibitory rate on both three pathogens (56.32-65.75 and 1.67-51.11%), notably the best suppression efficiency is presented in S61 and 40 mg/mL ethyl acetate extract. In terms of in vivo effects, both S61 and its ethyl acetate extract effectively reduced the decayed fruit and weight loss rate (0-20% and 7.59-16.56%) and enhanced the defensive enzymatic activities to improve resistance. In addition, strain S61 could be colonized on potato tubers, especially the highest amount of 1.55 × 10 CFU/mL on fifth day for variety Xiazhai 65. Overall, S61 and its ethyl acetate extract could be considered as potential approach for biocontrol potato dry rot.
Topics: Fungi; Halobacillus; Solanum tuberosum
PubMed: 35164641
DOI: 10.1080/21655979.2021.2024375 -
International Journal of Systematic and... Nov 2021An aerobic, Gram-stain-positive, endospore-forming, rod-shaped and moderately halophilic strain SKP4-6, was isolated from shrimp paste () collected from Samut Sakhon...
An aerobic, Gram-stain-positive, endospore-forming, rod-shaped and moderately halophilic strain SKP4-6, was isolated from shrimp paste () collected from Samut Sakhon Province, Thailand. Phylogenetic analysis revealed that strain SKP4-6 belonged to the genus and was most closely related to JCM 11546 (98.6 %), KCTC 3788 (98.6 %) and KCTC 3957 (98.6 %) based on 16S rRNA gene sequence similarity. The digital DNA-DNA hybridization (dDDH) and average nucleotide identity (ANI) values between strain SKP4-6 and its related species were 18.2-19.3 % and 69.84-84.51 %, respectively, which were lower than the threshold recommended for species delineation. The strain grew optimally at 30-40 °C, at pH 7.0 and with 10-15 % (w/v) NaCl. It contained l-Orn-d-Asp in the cell wall peptidoglycan. The DNA G+C content was 44.8 mol%. The major fatty acids were iso-C, anteiso-C and anteiso-C. The predominant isoprenoid quinone was MK-7. Phosphatidylglycerol and diphosphatidylglycerol were present as major polar lipids. Based on this polyphasic approach, digital DNA-DNA relatedness and ANI values, strain SKP4-6 represents a novel species of the genus , for which the name sp. nov. is proposed. The type strain is SKP4-6 (=JCM 32624=TISTR 2595).
Topics: Bacterial Typing Techniques; Base Composition; DNA, Bacterial; Fatty Acids; Food Microbiology; Halobacillus; Nucleic Acid Hybridization; Phospholipids; Phylogeny; RNA, Ribosomal, 16S; Seafood; Sequence Analysis, DNA; Thailand; Vitamin K 2
PubMed: 34825883
DOI: 10.1099/ijsem.0.005054