Biomaterial Database

Two proteins, YfiA and YhbH, associated with resting ribosomes in stationary phase Escherichia coli. 2000

Y Maki, and H Yoshida, and A Wada

Japan Science and Technology Corporation, Kawaguchi, Saitama 332-0012, Japan. ymaki@art.osaka-med.ac.jp

BACKGROUND Ribosomes in Escherichia coli change their composition and conformation in the stationary phase. Ribosome modulation factor (RMF) and ribosomal protein S22 are known to be associated with stationary phase ribosomes. RMF association causes the loss of translational activity and the dimerization of 70S ribosomes into 100S ribosomes, which may increase cell survival in the stationary phase. RESULTS Two weakly acidic proteins having related amino acid sequences were found to be associated with E. coli ribosomes in the stationary phase. These proteins are the products of ORFs named yfiA and yhbH. The sum of the copy numbers of their product proteins, YfiA and YhbH, in the ribosomal particles was low in the log phase, but increased to nearly one in the stationary phase. YfiA was found in the 70S ribosomal fraction rather than the 100S. On the other hand, YhbH was detected exclusively in the 100S ribosomal fraction. When the stationary phase cells were transferred to fresh medium, YfiA and YhbH were found in the 70S ribosomal fraction, but not in the polysome fraction. CONCLUSIONS Two proteins, YfiA and YhbH, associated with E. coli ribosomes were found to accumulate in the stationary phase, leading to the formation of several types of ribosomes. They are not likely to have roles in the elongation step of the translation in log phase cells, but are likely to be involved in the stabilization and preservation of ribosomes in the stationary phase, which might be necessary for cell survival.

UI	MeSH Term	Description	Entries
D008969	Molecular Sequence Data	Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.	Sequence Data, Molecular,Molecular Sequencing Data,Data, Molecular Sequence,Data, Molecular Sequencing,Sequencing Data, Molecular
D011485	Protein Binding	The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments.	Plasma Protein Binding Capacity,Binding, Protein
D003470	Culture Media	Any liquid or solid preparation made specifically for the growth, storage, or transport of microorganisms or other types of cells. The variety of media that exist allow for the culturing of specific microorganisms and cell types, such as differential media, selective media, test media, and defined media. Solid media consist of liquid media that have been solidified with an agent such as AGAR or GELATIN.	Media, Culture
D004926	Escherichia coli	A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.	Alkalescens-Dispar Group,Bacillus coli,Bacterium coli,Bacterium coli commune,Diffusely Adherent Escherichia coli,E coli,EAggEC,Enteroaggregative Escherichia coli,Enterococcus coli,Diffusely Adherent E. coli,Enteroaggregative E. coli,Enteroinvasive E. coli,Enteroinvasive Escherichia coli
D000595	Amino Acid Sequence	The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.	Protein Structure, Primary,Amino Acid Sequences,Sequence, Amino Acid,Sequences, Amino Acid,Primary Protein Structure,Primary Protein Structures,Protein Structures, Primary,Structure, Primary Protein,Structures, Primary Protein
D001426	Bacterial Proteins	Proteins found in any species of bacterium.	Bacterial Gene Products,Bacterial Gene Proteins,Gene Products, Bacterial,Bacterial Gene Product,Bacterial Gene Protein,Bacterial Protein,Gene Product, Bacterial,Gene Protein, Bacterial,Gene Proteins, Bacterial,Protein, Bacterial,Proteins, Bacterial
D012269	Ribosomal Proteins	Proteins found in ribosomes. They are believed to have a catalytic function in reconstituting biologically active ribosomal subunits.	Proteins, Ribosomal,Ribosomal Protein,Protein, Ribosomal
D012270	Ribosomes	Multicomponent ribonucleoprotein structures found in the CYTOPLASM of all cells, and in MITOCHONDRIA, and PLASTIDS. They function in PROTEIN BIOSYNTHESIS via GENETIC TRANSLATION.	Ribosome
D029968	Escherichia coli Proteins	Proteins obtained from ESCHERICHIA COLI.	E coli Proteins