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Microbial Ecology May 2024Water-filled sinkholes known locally as cenotes, found on the Yucatán Peninsula, have remarkable biodiversity. The primary objective of this study was to explore the...
Water-filled sinkholes known locally as cenotes, found on the Yucatán Peninsula, have remarkable biodiversity. The primary objective of this study was to explore the biotechnological potential of Gram-positive cultivable bacteria obtained from sediment samples collected at the coastal cenote Pol-Ac in Yucatán, Mexico. Specifically, the investigation aimed to assess production of hydrolytic enzymes and antimicrobial compounds. 16 S rRNA gene sequencing led to the identification of 49 Gram-positive bacterial isolates belonging to the phyla Bacillota (n = 29) and Actinomycetota (n = 20) divided into the common genera Bacillus and Streptomyces, as well as the genera Virgibacillus, Halobacillus, Metabacillus, Solibacillus, Neobacillus, Rossellomorea, Nocardiopsis and Corynebacterium. With growth at 55ºC, 21 of the 49 strains were classified as moderately thermotolerant. All strains were classified as halotolerant and 24 were dependent on marine water for growth. Screening for six extracellular hydrolytic enzymes revealed gelatinase, amylase, lipase, cellulase, protease and chitinase activities in 93.9%, 67.3%, 63.3%, 59.2%, 59.2% and 38.8%, of isolated strains, respectively. The genes for polyketide synthases type I, were detected in 24 of the strains. Of 18 strains that achieved > 25% inhibition of growth in the bacterial pathogen Staphylococcus aureus ATCC 6538, 4 also inhibited growth in Escherichia coli ATCC 35,218. Isolates Streptomyces sp. NCA_378 and Bacillus sp. NCA_374 demonstrated 50-75% growth inhibition against at least one of the two pathogens tested, along with significant enzymatic activity across all six extracellular enzymes. This is the first comprehensive report on the biotechnological potential of Gram-positive bacteria isolated from sediments in the cenotes of the Yucatán Peninsula.
Topics: Geologic Sediments; Mexico; Biodiversity; Gram-Positive Bacteria; RNA, Ribosomal, 16S; Bioprospecting; Phylogeny; Anti-Bacterial Agents; Seawater
PubMed: 38806738
DOI: 10.1007/s00248-024-02392-1 -
Microorganisms Feb 2024Soil salinization is negatively affecting soils globally, and the spread of this problem is of great concern due to the loss of functions and benefits offered by the...
Soil salinization is negatively affecting soils globally, and the spread of this problem is of great concern due to the loss of functions and benefits offered by the soil resource. In the present study, we explored the diversity of halophilic and halotolerant microorganisms in the arable fraction of a sodic-saline soil without agricultural practices and two soils with agricultural practices (one sodic and one saline) near the geothermal area "Los Negritos" in Villamar, Michoacán state. This was achieved through their isolation and molecular identification, as well as the characterization of their potential for the production of metabolites and enzymes of biotechnological interest under saline conditions. Using culture-dependent techniques, 62 halotolerant and moderately halophilic strains belonging to the genera , , , , , , , , , , , , , , , , and were isolated. The different strains synthesized hydrolytic enzymes under 15% (/) of salts, as well as metabolites with plant-growth-promoting (PGP) characteristics, such as indole acetic acid (IAA), under saline conditions. Furthermore, the production of biopolymers was detected among the strains; members of , , , and showed extracellular polymeric substance (EPS) production, and the strain sp. LNSP3E3-1.2 produced polyhydroxybutyrate (PHB) under 10% (/) of total salts.
PubMed: 38543532
DOI: 10.3390/microorganisms12030482 -
Foods (Basel, Switzerland) Nov 2023Protein malnutrition is present in developing countries but also in developed ones due to actual eating habits involving insufficient protein intake. In addition to... (Review)
Review
Protein malnutrition is present in developing countries but also in developed ones due to actual eating habits involving insufficient protein intake. In addition to this, it is estimated by the Food and Agricultural Organization of the United Nations that the world's population will increase to 9.1 billion people in less than 30 years. This poses a significant challenge in terms of nourishing the population. Different strategies have been proposed to address this challenge, including exploring novel protein sources such as plants. For instance, Prosopis alba pods have an 85.5% protein content. Other examples are microorganisms, such as which produces 571 U/mL of protease, and insects such as those belonging to the Orthoptera order, like grasshoppers, which have a protein content of 65.96%. These sources have been found in dry lands and are being explored to address this challenge.
PubMed: 38231705
DOI: 10.3390/foods12234284 -
Microbiology Resource Announcements Feb 2024We report here the genome sequence of moderately halophilic ASL-17, isolated from hypersaline sediment from the Yellow Sea, Korea. The bacterium was Gram variable, oval...
We report here the genome sequence of moderately halophilic ASL-17, isolated from hypersaline sediment from the Yellow Sea, Korea. The bacterium was Gram variable, oval or coccoid, and mesophilic. The genome of ASL-17 has 3.8 Mbp, with 3,910 coding sequences, 76 RNAs, and 41.3% G + C content.
PubMed: 38206017
DOI: 10.1128/mra.00692-23 -
International Journal of Systematic and... Oct 2023Three bacterial strains, designated SSBR10-3, SSTM10-2 and SSHM10-5, were isolated from saltern soil sampled in Jeollanam-do, Republic of Korea. Cells were aerobic,...
Three bacterial strains, designated SSBR10-3, SSTM10-2 and SSHM10-5, were isolated from saltern soil sampled in Jeollanam-do, Republic of Korea. Cells were aerobic, Gram-stain-positive, flagellated and rod-shaped. The strains grew optimally at 28°C and at pH 7.0. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strains SSBR10-3, SSTM10-2 and SSHM10-5 were placed within the genus , showing the highest similarity to FP5 (98.6 %), '' Marseille-Q1234 (98.5 %) and MSS-155 (98.6 %), respectively. The genomic similarity values between strains SSBR10-3, SSTM10-2 and SSHM10-5 and their related species were 17.6-22.6 % for digital DNA-DNA hybridization (dDDH) and 69.6-78.5 % for orthologous average nucleotide identity (OrthoANI), which were lower than the thresholds recommended for species delineation. The dDDH and OrthoANI values among the three strains were below 38.3 and 89.4 %, respectively. Besides the differences in genomic features, strains SSBR10-3, SSTM10-2 and SSHM10-5 were distinct from each other and from members of the genus in terms of phenotypic traits related to substrate assimilation. The cell-wall peptidoglycan contained -diaminopimelic acid, the major fatty acids were anteiso-C, iso-C and anteiso-C, and the predominant menaquinone was MK-7 for all three strains. Diphosphatidylglycerol, phosphatidylglycerol and an unidentified phospholipid were present in their polar lipid profiles. Based on a polyphasic approach incorporating genomic data, strains SSBR10-3, SSTM10-2 and SSHM10-5 represent novel species, for which the names sp. nov. (SSBR10-3=DSM 114353=KACC 21935=NBRC 115504), sp. nov. (SSTM10-2=DSM 114354=KACC 21936=NBRC 115505) and sp. nov. (SSHM10-5=DSM 114355= KACC 21937=NBRC 115506) are proposed.
Topics: Fatty Acids; Halobacillus; Phylogeny; RNA, Ribosomal, 16S; Sequence Analysis, DNA; DNA, Bacterial; Bacterial Typing Techniques; Base Composition; Nucleotides
PubMed: 37882660
DOI: 10.1099/ijsem.0.006098 -
Microbiology Resource Announcements Nov 2023We present the whole-genome sequence of Korean Agricultural Culture Collection (KACC) 21980, isolated from China by Chen et al.. The genome of KACC 21980 comprises a...
We present the whole-genome sequence of Korean Agricultural Culture Collection (KACC) 21980, isolated from China by Chen et al.. The genome of KACC 21980 comprises a circular chromosome (4.2 Mb) and one plasmid (17 kb). It includes a total of 4,168 predicted coding genes.
PubMed: 37874147
DOI: 10.1128/MRA.00570-23 -
Journal, Genetic Engineering &... May 2023Hydrolytic enzymes from halophilic microorganisms have a wide range of industrial applications. Herein, we report the isolation of Halobacillus sp. HAL1, a moderately...
Optimization, partial purification, and characterization of a novel high molecular weight alkaline protease produced by Halobacillus sp. HAL1 using fish wastes as a substrate.
BACKGROUND
Hydrolytic enzymes from halophilic microorganisms have a wide range of industrial applications. Herein, we report the isolation of Halobacillus sp. HAL1, a moderately halophilic bacterium that produces a novel high molecular weight extracellular alkaline protease when grown in fish processing wastes as a substrate.
RESULTS
Results showed that the isolated strain belonged to the genus Halobacillus, and it was designated as Halobacillus sp. HAL1 with the GenBank accession number OK001470. The strain secreted an extracellular alkaline protease, and the highest yield was obtained when it was grown in a medium with fish wastes substrate as the sole nutritional source (10 g/L) and incubated at 25 °C under shaking conditions. The enzyme was partially purified by Sephadex G-100 column chromatography. Zymographic analysis showed two casein degrading bands of about 190 and 250 KDa. The optimum enzyme activity was at a temperature of 50 °C at pH 8. The proteolytic activity was enhanced in the presence of metal ions (Ca, Mg, and Mn), surfactants (Tween 80, SDS, and Triton-X100), HO, and EDTA.
CONCLUSION
Our study indicates that Haobacillus sp. HAL1 is a moderately halophilic strain and secrets a novel high molecular wight alkaline protease that is suitable for detergent formulation.
PubMed: 37121925
DOI: 10.1186/s43141-023-00509-6 -
Environmental Microbiome Mar 2023The adaptability of halophytes to increased soil salinity is related to complex rhizosphere interactions. In this study, an integrative approach, combining...
The adaptability of halophytes to increased soil salinity is related to complex rhizosphere interactions. In this study, an integrative approach, combining culture-independent and culture-dependent techniques was used to analyze the bacterial communities in the endorizosphere of indigenous succulent halophytes Salicornia europaea, Suaeda maritima, and Camphorosma annua from the natural salt marshes of Slano Kopovo (Serbia). The 16 S rDNA analyses gave, for the first time, an insight into the composition of the endophytic bacterial communities of S. maritima and C. annua. We have found that the composition of endophyte microbiomes in the same habitat is to some extent influenced by plant species. A cultivable portion of the halophyte microbiota was tested at different NaCl concentrations for the set of plant growth promoting (PGP) traits. Through the mining of indigenous halotolerant endophytes, we obtained a collection representing a core endophyte microbiome conferring desirable PGP traits. The majority (65%) of the selected strains belonged to the common halotolerant/halophilic genera Halomonas, Kushneria, and Halobacillus, with representatives exhibiting multiple PGP traits, and retaining beneficial traits in conditions of the increased salinity. The results suggest that the root endosphere of halophytes is a valuable source of PGP bacteria supporting plant growth and fitness in salt-affected soils.
PubMed: 36934265
DOI: 10.1186/s40793-023-00477-x -
Environmental Microbiome Dec 2022Lake Hillier is a hypersaline lake known for its distinctive bright pink color. The cause of this phenomenon in other hypersaline sites has been attributed to...
Lake Hillier is a hypersaline lake known for its distinctive bright pink color. The cause of this phenomenon in other hypersaline sites has been attributed to halophiles, Dunaliella, and Salinibacter, however, a systematic analysis of the microbial communities, their functional features, and the prevalence of pigment-producing-metabolisms has not been previously studied. Through metagenomic sequencing and culture-based approaches, our results evidence that Lake Hillier is composed of a diverse set of microorganisms including archaea, bacteria, algae, and viruses. Our data indicate that the microbiome in Lake Hillier is composed of multiple pigment-producer microbes, including Dunaliella, Salinibacter, Halobacillus, Psychroflexus, Halorubrum, many of which are cataloged as polyextremophiles. Additionally, we estimated the diversity of metabolic pathways in the lake and determined that many of these are related to pigment production. We reconstructed complete or partial genomes for 21 discrete bacteria (N = 14) and archaea (N = 7), only 2 of which could be taxonomically annotated to previously observed species. Our findings provide the first metagenomic study to decipher the source of the pink color of Australia's Lake Hillier. The study of this pink hypersaline environment is evidence of a microbial consortium of pigment producers, a repertoire of polyextremophiles, a core microbiome and potentially novel species.
PubMed: 36544228
DOI: 10.1186/s40793-022-00455-9 -
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