Cross-functionalities of Bacillus deacetylases involved in bacillithiol biosynthesis and bacillithiol-S-conjugate detoxification pathways

2013 ◽  
Vol 454 (2) ◽  
pp. 239-247 ◽  
Author(s):  
Zhong Fang ◽  
Alexandra A. Roberts ◽  
Karissa Weidman ◽  
Sunil V. Sharma ◽  
Al Claiborne ◽  
...  
Keyword(s):  
Bacillus Cereus ◽  
Bacillus Anthracis ◽  
Kinetic Analysis ◽  
Genomic Analysis ◽  
Activity Profile ◽  
Acid Base ◽  
Key Enzyme ◽  
Acetyl Group ◽  
High Degree ◽  
Detoxification Pathways

BshB, a key enzyme in bacillithiol biosynthesis, hydrolyses the acetyl group from N-acetylglucosamine malate to generate glucosamine malate. In Bacillus anthracis, BA1557 has been identified as the N-acetylglucosamine malate deacetylase (BshB); however, a high content of bacillithiol (~70%) was still observed in the B. anthracis ∆BA1557 strain. Genomic analysis led to the proposal that another deacetylase could exhibit cross-functionality in bacillithiol biosynthesis. In the present study, BA1557, its paralogue BA3888 and orthologous Bacillus cereus enzymes BC1534 and BC3461 have been characterized for their deacetylase activity towards N-acetylglucosamine malate, thus providing biochemical evidence for this proposal. In addition, the involvement of deacetylase enzymes is also expected in bacillithiol-detoxifying pathways through formation of S-mercapturic adducts. The kinetic analysis of bacillithiol-S-bimane conjugate favours the involvement of BA3888 as the B. anthracis bacillithiol-S-conjugate amidase (Bca). The high degree of specificity of this group of enzymes for its physiological substrate, along with their similar pH–activity profile and Zn2+-dependent catalytic acid–base reaction provides further evidence for their cross-functionalities.

scholarly journals Highly Efficient Biosynthesis of Indole-3-acetic acid by Enterobacter xiangfangensis BHW6

2020 ◽  
Author(s):  
Bi-Xian Zhang ◽  
Ying-Ying Wang ◽  
Xiaomei Hu
Keyword(s):  
Acetic Acid ◽  
Economic Value ◽  
Pyruvate Decarboxylase ◽  
Genomic Analysis ◽  
Rrna Gene ◽  
H Nmr ◽  
Gene Coding ◽  
Key Enzyme ◽  
Indole 3 Acetic Acid ◽  
Iaa Biosynthesis

Abstract Background: Indole-3-acetic acid (IAA) plays an important role in the growth and development of plants. Various bacteria in the rhizosphere are capable to produce IAA that acts as a signaling molecule for the communication between plants and microbes to promote the plant growth. Due to the low IAA content and various interfering analogs, it is difficult to detect and isolate IAA from microbial secondary metabolites. Results: A predominant strain with a remarkable capability to secrete IAA was identified as Enterobacter xiangfangensis BHW6 based on 16S rRNA gene sequence, the determination of average nucleotide identity (ANI) and digital DDH (dDDH). The maximum IAA content (134-1129 μg/mL) was found with the addition of 0.2-15 g/L of L-tryptophan at pH 5 for 6 days, which was 4-40 fold higher than that in the absence of L-tryptophan. The highest yield of IAA was obtained at the stationary phase of bacterial growth. An acidic culture medium was preferred for the IAA biosynthesis of the strain. The strain was tolerant and stable to produce IAA in the presence 2.5%-5% (w/v) of NaCl. IAA was then isolated through column chromatography with a mobile phase of hexane/ethyl acetate (1/2, v/v) and characterized by 1H Nuclear Magnetic Resonance (1H NMR). Conclusions: A remarkable IAA production was obtained from E. xiangfangensis BHW6 that was tryptophan–dependent. According to genomic analysis, the ipdC gene coding for the key enzyme (indole-3-pyruvate decarboxylase) was identified indicating that IAA biosynthesis was mainly through the indole-3-pyruvia acid (IPyA) pathway, which was further confirmed by intermediate assay. E. xiangfangensis BHW6 with an important economic value has great prospect in agricultural and industrial application.

scholarly journals Fine-scale differentiation between Bacillus anthracis and Bacillus cereus group signatures in metagenome shotgun data

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e5515 ◽  
Author(s):  
Robert A. Petit III ◽  
James M. Hogan ◽  
Matthew N. Ezewudo ◽  
Sandeep J. Joseph ◽  
Timothy D. Read
Keyword(s):  
New York ◽  
New York City ◽  
Bacillus Cereus ◽  
Bacillus Anthracis ◽  
Genome Sequence ◽  
York City ◽  
False Positive ◽  
Lethal Factor ◽  
Analysis Tool ◽  
Sequencing Errors

Background It is possible to detect bacterial species in shotgun metagenome datasets through the presence of only a few sequence reads. However, false positive results can arise, as was the case in the initial findings of a recent New York City subway metagenome project. False positives are especially likely when two closely related are present in the same sample. Bacillus anthracis, the etiologic agent of anthrax, is a high-consequence pathogen that shares >99% average nucleotide identity with Bacillus cereus group (BCerG) genomes. Our goal was to create an analysis tool that used k-mers to detect B. anthracis, incorporating information about the coverage of BCerG in the metagenome sample. Methods Using public complete genome sequence datasets, we identified a set of 31-mer signatures that differentiated B. anthracis from other members of the B. cereus group (BCerG), and another set which differentiated BCerG genomes (including B. anthracis) from other Bacillus strains. We also created a set of 31-mers for detecting the lethal factor gene, the key genetic diagnostic of the presence of anthrax-causing bacteria. We created synthetic sequence datasets based on existing genomes to test the accuracy of a k-mer based detection model. Results We found 239,503 B. anthracis-specific 31-mers (the Ba31 set), 10,183 BCerG 31-mers (the BCerG31 set), and 2,617 lethal factor k-mers (the lef31 set). We showed that false positive B. anthracis k-mers—which arise from random sequencing errors—are observable at high genome coverages of B. cereus. We also showed that there is a “gray zone” below 0.184× coverage of the B. anthracis genome sequence, in which we cannot expect with high probability to identify lethal factor k-mers. We created a linear regression model to differentiate the presence of B. anthracis-like chromosomes from sequencing errors given the BCerG background coverage. We showed that while shotgun datasets from the New York City subway metagenome project had no matches to lef31 k-mers and hence were negative for B. anthracis, some samples showed evidence of strains very closely related to the pathogen. Discussion This work shows how extensive libraries of complete genomes can be used to create organism-specific signatures to help interpret metagenomes. We contrast “specialist” approaches to metagenome analysis such as this work to “generalist” software that seeks to classify all organisms present in the sample and note the more general utility of a k-mer filter approach when taxonomic boundaries lack clarity or high levels of precision are required.

scholarly journals Bovine Bacillus anthracis in Cameroon

2011 ◽  
Vol 77 (16) ◽  
pp. 5818-5821 ◽  
Author(s):  
Paola Pilo ◽  
Alexandra Rossano ◽  
Hamadou Bamamga ◽  
Souley Abdoulkadiri ◽  
Vincent Perreten ◽  
...  
Keyword(s):  
Bacillus Cereus ◽  
Bacillus Anthracis ◽  
Content Type ◽  
Western Africa

ABSTRACTBovineBacillus anthracisisolates from Cameroon were genetically characterized. They showed a strong homogeneity, and they belong, together with strains from Chad, to cluster Aβ, which appears to be predominant in western Africa. However, one strain that belongs to a newly defined clade (D) and cluster (D1) is penicillin resistant and shows certain phenotypes typical ofBacillus cereus.

scholarly journals Genome sequence of Bacillus cereus and comparative analysis with Bacillus anthracis

Nature ◽  
2003 ◽  
Vol 423 (6935) ◽  
pp. 87-91 ◽  
Author(s):  
Natalia Ivanova ◽  
Alexei Sorokin ◽  
Iain Anderson ◽  
Nathalie Galleron ◽  
Benjamin Candelon ◽  
...  
Keyword(s):  
Comparative Analysis ◽  
Bacillus Cereus ◽  
Bacillus Anthracis ◽  
Genome Sequence

scholarly journals Characterization and genomic analysis of chromate resistant and reducing Bacillus cereus strain SJ1

2010 ◽  
Vol 10 (1) ◽  
Author(s):  
Minyan He ◽  
Xiangyang Li ◽  
Liang Guo ◽  
Susan J Miller ◽  
Christopher Rensing ◽  
...  
Keyword(s):  
Bacillus Cereus ◽  
Genomic Analysis

Structure and water durability of tin(II) organosilicophosphate glasses prepared by nonaqueous acid–base reactions

2006 ◽  
Vol 21 (7) ◽  
pp. 1798-1806 ◽  
Author(s):  
Megumi Mizuno ◽  
Masahide Takahashi ◽  
Toshinobu Yoko
Keyword(s):  
Room Temperature ◽  
Orthophosphoric Acid ◽  
Chain Structure ◽  
Acid Base ◽  
Humid Atmosphere ◽  
Water Durability ◽  
Magnetic Resonance Technique ◽  
A Chain ◽  
Degree Of Condensation ◽  
High Degree

Tin(II) organosilicophosphate glasses were prepared by nonaqueous acid–base reactions using orthophosphoric acid, dimethyldichlorosilane, and tin(II)chloride as the starting materials. The structure of the methylsiloxane-phosphate copolymer (methylsilicophosphate) and tin(II) methylsilicophosphate glasses was mainly investigated by the 31P nuclear magnetic resonance technique. A chain structure composed of the –(P–O–Si–O)m– silicophosphate bonds was found as the main structural unit in the methylsilicophosphate prepared by mixing orthophosphoric acid and dimethyldichlorosilane at room temperature. Tin(II) methylsilicophosphate glasses could be prepared by introducing SnCl2 as a cross-linking agent of silicophosphate chains. By increasing the reaction temperature, it was possible to promote the reaction and then to increase the network dimensions of the resultant tin(II) methylsilicophosphate glasses. It was found that the glasses with a high degree of condensation tend to have a better water durability in a humid atmosphere.

Sign in / Sign up

Export Citation Format

Share Document