The regulatory gene levR of the levanase operon of Bacillus subtilis was cloned and sequenced. It encodes a polypeptide of Mr 106,064 with two domains homologous to members of two families of bacterial activators. One domain in LevR is homologous with one region of bacterial regulators including SacT and SacY of B. subtilis and BglG from Escherichia coli. Another domain of LevR is homologous to one part of the central domain of NifA and NtrC, which control nitrogen assimilation in Gram-negative bacteria. The levanase promoter contains two regions almost identical to the -12, -24 consensus regions present in sigma 54-dependent promoters. The expression of the levanase operon in E. coli was strongly dependent on sigma 54. Taken together, these results suggest that the operon is expressed from a -12, -24 promoter regulated by a sigma 54-like-dependent system in B. subtilis.
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http://dx.doi.org/10.1073/pnas.88.6.2212 | DOI Listing |
J Agric Food Chem
January 2025
School of Food and Biological Engineering, Jiangsu University, 301 Xuefu Road, Zhenjiang, Jiangsu 212013, PR China.
D-Allose, a rare sugar, has gained significant attention not only as a low-calorie sweetener but also for its anticancer, antitumor, anti-inflammatory, antioxidant, and other pharmaceutical properties. Despite its potential, achieving high-level biosynthesis of D-allose remains challenging due to inefficient biocatalysts, low conversion rates, and the high cost of substrates. Here, we explored the food-grade coexpression of D-allulose 3-epimerase (Bp-DAE) and L-rhamnose isomerase (BsL-RI) within a single cell using WB800N as the host.
View Article and Find Full Text PDFNat Microbiol
January 2025
Department of Chemistry, Indiana University, Bloomington, IN, USA.
To overtake competitors, microbes produce and secrete secondary metabolites that kill neighbouring cells and sequester nutrients. This metabolite-mediated competition probably evolved in complex microbial communities in the presence of viral pathogens. We therefore hypothesized that microbes secrete natural products that make competitors sensitive to phage infection.
View Article and Find Full Text PDFFood Res Int
January 2025
State Key Laboratory of Food Science and Resources, National Engineering Research Center of Cereal Fermentation and Food Biomanufacturing, School of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, China; Guangdong Engineering Research Center of High-Value Utilization and Equipment Development of Marine Biological Resources, Southern Marine Science and Engineering Guangdong Laboratory, Guangzhou, Guangdong 511458, China; Jiangnan University (Shaoxing) Industrial Technology Research Institute, Shaoxing, Zhejiang 31200, China; National Engineering Research Center of Huangjiu, Zhejiang Guyuelongshan Shaoxing Wine CO., LTD, Shaoxing 646000, Zhejiang, China. Electronic address:
To explore the mechanism of Virgibacillus proteases on hydrolysis of shrimp myofibrillar protein (SMP) and formation of volatile compounds, the fermented broth of Virgibacillus halodenitrificans was purified and the protease was identified as peptidase S8. The enzyme had optimum activity at pH 7.0-8.
View Article and Find Full Text PDFJ Appl Microbiol
January 2025
ICAR-Indian Institute of Horticultural Research, Hessaraghatta Lake Post, Bengaluru 560089, India.
Aim: Bacillus subtilis is usually found in soil, and their biocontrol and plant growth promoting capabilities are being explored more recently than ever. However, knowledge about metabolite production and genome composition of endophytic Bacillus subtilis from seeds is limited. In the present study, Bacillus subtilis EVCu15 strain isolated from the seeds of Vasconcellea cundinamarcensis (mountain papaya) was subjected to whole genome sequencing, and detailed molecular and functional characterization.
View Article and Find Full Text PDFNucleic Acids Res
January 2025
Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, No. 1800, Lihu Avenue, Binhu District, Wuxi 214122, China.
Developing efficient gene regulation tools is essential for optimizing microbial cell factories, but most existing tools only modulate gene expression at the transcriptional level. Regulation at the translational level provides a faster dynamic response, whereas developing a programmable, efficient and multiplexed translational regulation tool remains a challenge. Here, we have developed CRISPRi and CRISPRa systems based on hfCas13X that can regulate gene translation in Bacillus subtilis.
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