scholarly journals Ribosomal Hibernation-Associated Factors in Escherichia coli

2021 ◽  
Vol 10 (1) ◽  
pp. 33
Author(s):  
Yasushi Maki ◽  
Hideji Yoshida

Bacteria convert active 70S ribosomes to inactive 100S ribosomes to survive under various stress conditions. This state, in which the ribosome loses its translational activity, is known as ribosomal hibernation. In gammaproteobacteria such as Escherichia coli, ribosome modulation factor and hibernation-promoting factor are involved in forming 100S ribosomes. The expression of ribosome modulation factor is regulated by (p)ppGpp (which is induced by amino acid starvation), cAMP-CRP (which is stimulated by reduced metabolic energy), and transcription factors involved in biofilm formation. This indicates that the formation of 100S ribosomes is an important strategy for bacterial survival under various stress conditions. In recent years, the structures of 100S ribosomes from various bacteria have been reported, enhancing our understanding of the 100S ribosome. Here, we present previous findings on the 100S ribosome and related proteins and describe the stress-response pathways involved in ribosomal hibernation.

2009 ◽  
Vol 75 (6) ◽  
pp. 1723-1733 ◽  
Author(s):  
Claire Perrin ◽  
Romain Briandet ◽  
Gregory Jubelin ◽  
Philippe Lejeune ◽  
Marie-Andrée Mandrand-Berthelot ◽  
...  

ABSTRACT The survival of bacteria exposed to toxic compounds is a multifactorial phenomenon, involving well-known molecular mechanisms of resistance but also less-well-understood mechanisms of tolerance that need to be clarified. In particular, the contribution of biofilm formation to survival in the presence of toxic compounds, such as nickel, was investigated in this study. We found that a subinhibitory concentration of nickel leads Escherichia coli bacteria to change their lifestyle, developing biofilm structures rather than growing as free-floating cells. Interestingly, whereas nickel and magnesium both alter the global cell surface charge, only nickel promotes biofilm formation in our system. Genetic evidence indicates that biofilm formation induced by nickel is mediated by the transcriptional induction of the adhesive curli-encoding genes. Biofilm formation induced by nickel does not rely on efflux mechanisms using the RcnA pump, as these require a higher concentration of nickel to be activated. Our results demonstrate that the nickel-induced biofilm formation in E. coli is an adaptational process, occurring through a transcriptional effect on genes coding for adherence structures. The biofilm lifestyle is obviously a selective advantage in the presence of nickel, but the means by which it improves bacterial survival needs to be investigated.


2004 ◽  
Vol 70 (9) ◽  
pp. 5682-5684 ◽  
Author(s):  
Helena L. A. Vieira ◽  
Patrick Freire ◽  
Cecília M. Arraiano

ABSTRACT Biofilm physiology is established under a low growth rate. The morphogene bolA is mostly expressed under stress conditions or in stationary phase, suggesting that bolA could be implicated in biofilm development. In order to verify this hypothesis, we tested the effect of bolA on biofilm formation. Overexpression of bolA induces biofilm development, while bolA deletion decreases biofilms.


2021 ◽  
Vol 8 ◽  
Author(s):  
Hideji Yoshida ◽  
Hideki Nakayama ◽  
Yasushi Maki ◽  
Masami Ueta ◽  
Chieko Wada ◽  
...  

One of the important cellular events in all organisms is protein synthesis, which is catalyzed by ribosomes. The ribosomal activity is dependent on the environmental situation of the cell. Bacteria form 100S ribosomes, lacking translational activity, to survive under stress conditions such as nutrient starvation. The 100S ribosome is a dimer of two 70S ribosomes bridged through the 30S subunits. In some pathogens of gammaproteobacteria, such as Escherichia coli, Yersinia pestis, and Vibrio cholerae, the key factor for ribosomal dimerization is the small protein, ribosome modulation factor (RMF). When ribosomal dimerization by RMF is impaired, long-term bacterial survival is abolished. This shows that the interconversion system between active 70S ribosomes and inactive 100S ribosomes is an important survival strategy for bacteria. According to the results of several structural analyses, RMF does not directly connect two ribosomes, but binds to them and changes the conformation of their 30S subunits, thus promoting ribosomal dimerization. In this study, conserved RMF amino acids among 50 bacteria were selectively altered by mutagenesis to identify the residues involved in ribosome binding and dimerization. The activities of mutant RMF for ribosome binding and ribosome dimerization were measured using the sucrose density gradient centrifugation (SDGC) and western blotting methods. As a result, some essential amino acids of RMF for the ribosomal binding and dimerization were elucidated. Since the induction of RMF expression inhibits bacterial growth, the data on this protein could serve as information for the development of antibiotic or bacteriostatic agents.


2021 ◽  
Vol 4 (2) ◽  
pp. 166
Author(s):  
Ndaindila Haindongo ◽  
Amara Anyogu ◽  
Osmond Ekwebelem ◽  
Christian Anumudu ◽  
Helen Onyeaka

Biofilms are a significant concern in the food industry because of their potential to enhance bacterial survival and cause foodborne outbreaks. Escherichia coli (E. coli) is among the leading pathogens responsible for foodborne outbreaks and this can be attributed to its ability to form biofilms in food containers and food preparatory surfaces. The purpose of this study was to investigate the antibacterial and antibiofilm properties of garlic, ginger and mint and their potential to inhibit E.coli and biofilm formation. Disc diffusion assays and 96-well plate crystal violet-based methods were used to achieve these objectives. The plant extracts were diluted from 1 mg/ml to 0.1 mg/ml and incubated 25°C and 37°C to investigate the antimicrobial and antibiofilm effects on E. coli. The findings of this study showed that low temperatures induced the formation of E. coli biofilms and all tested extracts contain a broad spectrum of antibacterial and antibiofilm properties. This study provided new insights on the combined antimicrobial and antibiofilm properties of garlic, ginger and mint against planktonic cells and biofilms of E. coli MG 1655 and highlight the potential use of these extracts in the food industry to prevent biofilm formation by E. coli. 


2002 ◽  
Vol 132 (6) ◽  
pp. 983-989 ◽  
Author(s):  
H. Yoshida ◽  
Y. Maki ◽  
H. Kato ◽  
H. Fujisawa ◽  
K. Izutsu ◽  
...  

BMC Genomics ◽  
2019 ◽  
Vol 20 (1) ◽  
Author(s):  
Jarosław E. Król ◽  
Donald C. Hall ◽  
Sergey Balashov ◽  
Steven Pastor ◽  
Justin Sibert ◽  
...  

Abstract Background Escherichia coli C forms more robust biofilms than other laboratory strains. Biofilm formation and cell aggregation under a high shear force depend on temperature and salt concentrations. It is the last of five E. coli strains (C, K12, B, W, Crooks) designated as safe for laboratory purposes whose genome has not been sequenced. Results Here we present the complete genomic sequence of this strain in which we utilized both long-read PacBio-based sequencing and high resolution optical mapping to confirm a large inversion in comparison to the other laboratory strains. Notably, DNA sequence comparison revealed the absence of several genes thought to be involved in biofilm formation, including antigen 43, waaSBOJYZUL for lipopolysaccharide (LPS) synthesis, and cpsB for curli synthesis. The first main difference we identified that likely affects biofilm formation is the presence of an IS3-like insertion sequence in front of the carbon storage regulator csrA gene. This insertion is located 86 bp upstream of the csrA start codon inside the − 35 region of P4 promoter and blocks the transcription from the sigma32 and sigma70 promoters P1-P3 located further upstream. The second is the presence of an IS5/IS1182 in front of the csgD gene. And finally, E. coli C encodes an additional sigma70 subunit driven by the same IS3-like insertion sequence. Promoter analyses using GFP gene fusions provided insights into understanding this regulatory pathway in E. coli. Conclusions Biofilms are crucial for bacterial survival, adaptation, and dissemination in natural, industrial, and medical environments. Most laboratory strains of E. coli grown for decades in vitro have evolved and lost their ability to form biofilm, while environmental isolates that can cause infections and diseases are not safe to work with. Here, we show that the historic laboratory strain of E. coli C produces a robust biofilm and can be used as a model organism for multicellular bacterial research. Furthermore, we ascertained the full genomic sequence of this classic strain, which provides for a base level of characterization and makes it useful for many biofilm-based applications.


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