The nucleotide second messengers pppGpp and ppGpp [(p)ppGpp] are responsible for the global downregulation of transcription, translation, DNA replication, and growth rate that occurs during the stringent response. More recent studies suggest that (p)ppGpp is also an important effector in many nonstringent processes, including virulence, persister cell formation, and biofilm production. In Bacillus subtilis, (p)ppGpp production is primarily determined by the net activity of RelA, a bifunctional (p)ppGpp synthetase/hydrolase, and two monofunctional (p)ppGpp synthetases, YwaC and YjbM. We observe that in B. subtilis, a relA mutant grows exclusively as unchained, motile cells, phenotypes regulated by the alternative sigma factor SigD. Our data indicate that the relA mutant is trapped in a SigD "on" state during exponential growth, implicating RelA and (p)ppGpp levels in the regulation of cell chaining and motility in B. subtilis. Our results also suggest that minor variations in basal (p)ppGpp levels can significantly skew developmental decision-making outcomes.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4288673 | PMC |
http://dx.doi.org/10.1128/JB.02063-14 | DOI Listing |
Nat 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.
View Article and Find Full Text PDFArch Microbiol
January 2025
Key Laboratory of Aquaculture Nutrition and Feeds (Ministry of Agriculture and Rural Affairs), Key Laboratory of Mariculture (Ministry of Education), Fisheries College, Ocean University of China, 5 Yushan Road, 266003, Qingdao, P. R. China.
Brine shrimp nauplii are widely used as live food in fish and shellfish aquaculture but they may transmit pathogenic Vibrio to the target species causing significant economic loss. Heavy usage of antibiotics is expensive and environmentally damaging. Use of natural microbes as probiotics for disease management is a more sustainable strategy.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!