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Toxicology Research Nov 2019The environmental distribution of the neurotoxic amino acid, 3--methyl-2,3-diaminopropanoic acid (BMAA), first isolated in 1967, was initially believed to be limited to... (Review)
Review
The environmental distribution of the neurotoxic amino acid, 3--methyl-2,3-diaminopropanoic acid (BMAA), first isolated in 1967, was initially believed to be limited to tropical and subtropical plants of the genus The seeds of one such species, which had been used historically on the Pacific island of Guam as a foodstuff, had a reputation for neurotoxicity. Some 40 years later the amino acid was detected in terrestrial and aquatic cyanobacteria and in other aquatic organisms. Overlooked was the discovery of BMAA in peptides of bizarre structure that had been isolated in 1975 from during a search for antibiotics. More recently (2014), peptides of similar structure were isolated from ; this organism is causative of American Foulbrood, a lethal disease of honeybee colonies. These are interesting chemical and environmental observations, but knowledge of the bacterial distribution of BMAA is limited to just these two species of , while more than 200 spp. are known. spp. are ever present naturally in the environment and are used agriculturally; recent research reports that some species infect human foods - including cow's milk - and have been isolated from human body fluids. We wish to stimulate interest in the environmental distribution of the neurotoxic BMAA in spp. by drawing together previously isolated streams of research and by proposing experimental approaches by which this matter might be resolved.
PubMed: 32922737
DOI: 10.1039/c9tx00203k -
Archives of Microbiology Feb 2022Microbial-based products are a promising alternative to agrochemicals in sustainable agriculture. However, little is known about their impact on human health even if...
Microbial-based products are a promising alternative to agrochemicals in sustainable agriculture. However, little is known about their impact on human health even if some of them, i.e., Bacillus and Paenibacillus species, have been increasingly implicated in different human diseases. In this study, 18 bacteria were isolated from 2 commercial biostimulants, and they were genotypically and phenotypically characterized to highlight specific virulence properties. Some isolated bacteria were identified as belonging to the genus Bacillus by BLAST and RDP analyses, a genus in-depth studied for plant growth-promoting ability. Moreover, 16S rRNA phylogenetic analysis showed that seven isolates grouped with Bacillus species while two and four clustered, respectively, with Neobacillus and Peribacillus. Unusually, bacterial strains belonging to Franconibacter and Stenotrophomonas were isolated from biostimulants. Although Bacillus species are generally considered nonpathogenic, most of the species have shown to swim, swarm, and produced biofilms, that can be related to bacterial virulence. The evaluation of toxins encoding genes revealed that five isolates had the potential ability to produce the enterotoxin T. In conclusion, the pathogenic potential of microorganisms included in commercial products should be deeply verified, in our opinion. The approach proposed in this study could help in this crucial step.
Topics: Bacillus; Humans; Paenibacillus; Phylogeny; Plant Development; RNA, Ribosomal, 16S
PubMed: 35119529
DOI: 10.1007/s00203-022-02769-1 -
BioTechniques May 2024is a rich source of high-value natural components. Endophytic fungi are well studied, yet bacteria research is limited. In this study, endophytic bacteria from were...
is a rich source of high-value natural components. Endophytic fungi are well studied, yet bacteria research is limited. In this study, endophytic bacteria from were isolated using an improved method, showing inhibition of pathogens and growth promotion. JC-3jx, identified as , exhibited significant inhibitory activity against tested fungi and bacteria, including . JC-3jx also promoted corn seed rooting and growth, highlighting its excellent biocontrol and growth-promoting potential.
Topics: Dendrobium; Paenibacillus; Endophytes; Plant Roots; Zea mays
PubMed: 38469872
DOI: 10.2144/btn-2023-0083 -
Applied and Environmental Microbiology Nov 2018and are two bacteria that are members of the family. Both are commonly found in beehives and have historically been difficult to distinguish from each other due to...
and are two bacteria that are members of the family. Both are commonly found in beehives and have historically been difficult to distinguish from each other due to related genetic and phenotypic characteristics and a shared ecological niche. Here, we discuss the likely mischaracterization of three 16S rRNA sequences previously published as and provide the phylogenetic evidence that supported the GenBank reassignment of the sequences as We explore the issues that arise by using only 16S rRNA or other single-gene analyses to distinguish between these bacteria. We also present three sets of molecular markers, two sets that distinguish from and other closely related species within the genus and a third set that distinguishes from and other closely related species within the genus. These molecular markers provide a tool for proper identification of these oft-mistaken species. 16S rRNA gene sequencing in bacteria has long been held as the gold standard for typing bacteria and, for the most part, is an excellent method of taxonomically identifying different bacterial species. However, the high level of 16S rRNA sequence similarity of some published strains of and , as well as possible horizontal gene transfer events within their shared ecological niche, complicates the use of 16S rRNA sequence as an effective molecular marker for differentiating these two species. Additionally, shared characteristics of these bacteria limit the effectiveness of using traditional phenotypic identification assays, such as the catalase test. The results from this study provide PCR methods to quickly differentiate between these two genera and will be useful when studying , , and other disease-relevant bacteria commonly found in beehives.
Topics: Animals; Bacterial Typing Techniques; Bees; Brevibacillus; DNA, Bacterial; DNA, Ribosomal; Paenibacillus larvae; Phylogeny; Polymerase Chain Reaction; RNA, Ribosomal, 16S
PubMed: 30217838
DOI: 10.1128/AEM.01886-18 -
PloS One 2021Paenibacillus spp. exopolysaccharides (EPSs) have become a growing interest recently as a source of biomaterials. In this study, we characterized Paenibacillus polymyxa...
Paenibacillus spp. exopolysaccharides (EPSs) have become a growing interest recently as a source of biomaterials. In this study, we characterized Paenibacillus polymyxa 2020 strain, which produces a large quantity of EPS (up to 68 g/L),and was isolated from wasp honeycombs. Here we report its complete genome sequence and full methylome analysis detected by Pacific Biosciences SMRT sequencing. Moreover, bioinformatic analysis identified a putative levan synthetic operon. SacC and sacB genes have been cloned and their products identified as glycoside hydrolase and levansucrase respectively. The Fourier transform infrared (FT-IR) and nuclear magnetic resonance (NMR) spectra demonstrated that the EPS is a linear β-(2→6)-linked fructan (levan). The structure and properties of levan polymer produced from sucrose and molasses were analyzed by FT-IR, NMR, scanning electron microscopy (SEM), high performance size exclusion chromatography (HPSEC), thermogravimetric analysis (TGA), cytotoxicity tests and showed low toxicity and high biocompatibility. Thus, P. polymyxa 2020 could be an exceptional cost-effective source for the industrial production of levan-type EPSs and to obtain functional biomaterials based on it for a broad range of applications, including bioengineering.
Topics: Cloning, Molecular; Epigenome; Magnetic Resonance Spectroscopy; Microscopy, Electron, Scanning; Paenibacillus polymyxa; Polysaccharides, Bacterial; Sequence Analysis, DNA; Spectrometry, X-Ray Emission; Spectroscopy, Fourier Transform Infrared
PubMed: 34228741
DOI: 10.1371/journal.pone.0253482 -
Biocontrol Science 2021In this study, spore heat resistance and growth ability at refrigeration temperatures of Bacillus spp. and Paenibacillus spp. were determined. The spore D of 67.6% (23...
In this study, spore heat resistance and growth ability at refrigeration temperatures of Bacillus spp. and Paenibacillus spp. were determined. The spore D of 67.6% (23 of 34 strains) of Bacillus and 73.9% (17 of 23 strains) of Paenibacillus was less than 15 min. The growth abilities of both genera were equivalent at 10°C. However, 71.1% (32 of 45 strains) of Paenibacillus and only 6.3% (3 of 48 strains) of Bacillus cereus group could grow at 4°C. Eight B. cereus strains formed spores with higher heat resistance compared to the other Bacillus strains assessed; however, they did not grow at tempreratures below 10°C. Conversely, four Paenibacillus strains formed spores with heat resistance equivalent to that of the eight B. cereus strains and grew at 6°C or lower. In particular, Paenibacillus sp. JCM13343 formed the highest heat-resistant spores (D = 136.1 min) and grew well at 4°C. These results indicate that Paenibacillus can grow in processed foods during refrigerated storage and has the potential to cause spoilage as well as Bacillus. Therefore, Paenibacillus should be considered as one of the targets for microbiological control in refrigerated processed foods.
Topics: Bacillus; Bacillus cereus; Colony Count, Microbial; Food Microbiology; Hot Temperature; Paenibacillus; Refrigeration; Spores, Bacterial; Temperature
PubMed: 34556617
DOI: 10.4265/bio.26.147 -
MBio May 2017Antibiotic resistance is a prevalent problem in public health worldwide. In general, the carbapenem β-lactam antibiotics are considered a final resort against lethal...
Antibiotic resistance is a prevalent problem in public health worldwide. In general, the carbapenem β-lactam antibiotics are considered a final resort against lethal infections by multidrug-resistant bacteria. Colistin is a cationic polypeptide antibiotic and acts as the last line of defense for treatment of carbapenem-resistant bacteria. Very recently, a new plasmid-borne colistin resistance gene, , was revealed soon after the discovery of the paradigm gene , which has disseminated globally. However, the molecular mechanisms for MCR-2 colistin resistance are poorly understood. Here we show a unique transposon unit that facilitates the acquisition and transfer of Evolutionary analyses suggested that both MCR-2 and MCR-1 might be traced to their cousin phosphoethanolamine (PEA) lipid A transferase from a known polymyxin producer, Transcriptional analyses showed that the level of transcripts is relatively higher than that of Genetic deletions revealed that the transmembrane regions (TM1 and TM2) of both MCR-1 and MCR-2 are critical for their location and function in bacterial periplasm, and domain swapping indicated that the TM2 is more efficient than TM1. Matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) confirmed that all four MCR proteins (MCR-1, MCR-2, and two chimeric versions [TM1-MCR-2 and TM2-MCR-1]) can catalyze chemical modification of lipid A moiety anchored on lipopolysaccharide (LPS) with the addition of phosphoethanolamine to the phosphate group at the 4' position of the sugar. Structure-guided site-directed mutagenesis defined an essential 6-residue-requiring zinc-binding/catalytic motif for MCR-2 colistin resistance. The results further our mechanistic understanding of transferable colistin resistance, providing clues to improve clinical therapeutics targeting severe infections by MCR-2-containing pathogens. Carbapenem and colistin are the last line of refuge in fighting multidrug-resistant Gram-negative pathogens. MCR-2 is a newly emerging variant of the mobilized colistin resistance protein MCR-1, posing a potential challenge to public health. Here we report transfer of the gene by a unique transposal event and its possible origin. Distribution of MCR-2 in bacterial periplasm is proposed to be a prerequisite for its role in the context of biochemistry and the colistin resistance. We also define the genetic requirement of a zinc-binding/catalytic motif for MCR-2 colistin resistance. This represents a glimpse of transferable colistin resistance by MCR-2.
Topics: Anti-Bacterial Agents; Colistin; Crystallography, X-Ray; Drug Resistance, Bacterial; Escherichia; Escherichia coli Proteins; Mutagenesis, Site-Directed; Paenibacillus; Plasmids; Polymyxins; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
PubMed: 28487432
DOI: 10.1128/mBio.00625-17 -
Toxins Feb 2023An antibiotic produced by 7F1 was studied. The 7F1 strain was isolated from the rhizosphere of a wheat field. Response surface methodology was used to optimize the...
An antibiotic produced by 7F1 was studied. The 7F1 strain was isolated from the rhizosphere of a wheat field. Response surface methodology was used to optimize the physicochemical parameters. The strain showed broad-spectrum activity against several plant pathogens. Identification of the strain was realized based on 16s rRNA gene and gene sequencing. The antibiotic was optimized by one-factor-at-a-time (OFAT) and response surface methodology (RSM) approaches. The suitable antibiotic production conditions were optimized using the one-factor-at-a-time method. The individual and interaction effects of three independent variables: culture temperature, initial pH, and culture time, were optimized by Box-Behnken design. The 16SrRNA gene sequence (1239 nucleotides) and gene (1111 nucleotides) were determined for strain 7F1 and shared the highest identities to those of . The results showed the optimal fermentation conditions for antibiotics produced by 7F1 were a culture temperature of 38 °C, initial pH of 8.0, and culture time of 8 h. The antibiotics produced by 7F1 include lipopeptides such as iturin A and surfactin. The results provide a theoretical basis for the development of bacteriostatic biological agents and the control of mycotoxins.
Topics: Paenibacillus polymyxa; Fusarium; Anti-Bacterial Agents; RNA, Ribosomal, 16S; Fermentation
PubMed: 36828452
DOI: 10.3390/toxins15020138 -
Frontiers in Cellular and Infection... 2022To discover novel microbial pesticide for controlling rice bacterial disease, polymyxin B and E were firstly isolated from the supernatant of fermentation broth of by...
To discover novel microbial pesticide for controlling rice bacterial disease, polymyxin B and E were firstly isolated from the supernatant of fermentation broth of by bioactivity tracking separation. It is shown that polymyxin B and E had remarkable inhibitory activities to pv. () and pv. () with the EC values of 0.19 μg/ml and 0.21 μg/ml against , and 0.32 μg/ml and 0.41 μg/ml against , respectively, which were better than those of Zhongshengmycin (0.31 μg/ml and 0.73 μg/ml) and Bismerthiazol (77.48 μg/ml and 85.30 μg/ml). Polymyxins B and E had good protection and curative activities against rice bacterial leaf blight (BLB) and rice bacterial leaf streak (BLS) . The protection and curative activities of polymyxins B (45.8 and 35.8%, respectively) and E (41.2 and 37.0%, respectively) to BLB were superior to those of Zhongshengmycin (34.8 and 29.8%, respectively) and Bismerthiazol (38.0 and 33.5%, respectively). Meanwhile, the protection and curative activities of polymyxins B (44.8 and 39.8%, respectively) and E (42.9 and 39.9%, respectively) to BLS were also superior to those of Zhongshengmycin (39.7 and 32.0%, respectively) and Bismerthiazol (41.5 and 34.3%, respectively). Polymyxin B exerted the anti-pesticide properties destroying the cell integrity of , reducing its infectivity and enhancing rice resistance against pathogens through activating the phenylpropanoid biosynthesis pathway of rice. It is indicated that polymyxin B and E were potential microbial pesticides for controlling rice bacterial disease.
Topics: Anti-Bacterial Agents; Bacterial Infections; Oryza; Paenibacillus polymyxa; Plant Diseases; Polymyxins; Xanthomonas
PubMed: 35419296
DOI: 10.3389/fcimb.2022.866357 -
Nature Ecology & Evolution May 2018The growth and survival of organisms often depend on interactions between them. In many cases, these interactions are positive and caused by a cooperative modification...
The growth and survival of organisms often depend on interactions between them. In many cases, these interactions are positive and caused by a cooperative modification of the environment. Examples are the cooperative breakdown of complex nutrients in microbes or the construction of elaborate architectures in social insects, in which the individual profits from the collective actions of her peers. However, organisms can similarly display negative interactions by changing the environment in ways that are detrimental for them, for example by resource depletion or the production of toxic byproducts. Here we find an extreme type of negative interactions, in which Paenibacillus sp. bacteria modify the environmental pH to such a degree that it leads to a rapid extinction of the whole population, a phenomenon that we call ecological suicide. Modification of the pH is more pronounced at higher population densities, and thus ecological suicide is more likely to occur with increasing bacterial density. Correspondingly, promoting bacterial growth can drive populations extinct whereas inhibiting bacterial growth by the addition of harmful substances-such as antibiotics-can rescue them. Moreover, ecological suicide can cause oscillatory dynamics, even in single-species populations. We found ecological suicide in a wide variety of microbes, suggesting that it could have an important role in microbial ecology and evolution.
Topics: Environment; Hydrogen-Ion Concentration; Microbial Interactions; Paenibacillus; Population Dynamics
PubMed: 29662223
DOI: 10.1038/s41559-018-0535-1