Role of murF in cell wall biosynthesis: isolation and characterization of a murF conditional mutant of Staphylococcus aureus.
نویسندگان
چکیده
The Staphylococcus aureus murF gene was placed under the control of a promoter inducible by IPTG (isopropyl-beta-d-thiogalactopyranoside). It was demonstrated that murF is an essential gene; it is cotranscribed with ddlA and growth rate, level of beta-lactam antibiotic resistance, and rates of transcription of the mecA and pbpB genes paralleled the rates of transcription of murF. At suboptimal concentrations of the inducer, a UDP-linked muramyl tripeptide accumulated in the cytoplasm in parallel with the decline in the amounts of the normal pentapeptide cell wall precursor. The abnormal tripeptide component incorporated into the cell wall as a monomeric muropeptide, accompanied by a decrease in the oligomerization degree of the peptidoglycan. However, incorporation of the tripeptide into the cell wall was limited to a relatively low threshold value. Further reduction of the amounts of pentapeptide cell wall precursor caused a gradual decrease in the cellular amounts of peptidoglycan, the production of a thinner peripheral cell wall, aberrant septae, and an overall increase in the diameter of the cells. The observations suggest that the role of murF exceeds its primary function in peptidoglycan biosynthesis and may also be involved in the control of cell division.
منابع مشابه
Extensive and genome-wide changes in the transcription profile of Staphylococcus aureus induced by modulating the transcription of the cell wall synthesis gene murF.
A murF conditional mutant was used to evaluate the effect of suboptimal transcription of this gene on the transcriptome of the methicillin-resistant Staphylococcus aureus strain COL. The mutant was grown in the presence of optimal and suboptimal concentrations of the inducer, and the relative levels of transcription of genes were evaluated genome wide with an Affymetrix DNA microarray that incl...
متن کاملUtility of muropeptide ligase for identification of inhibitors of the cell wall biosynthesis enzyme MurF.
MurF is a key enzyme in the biosynthesis of the bacterial cell wall in both gram-positive and gram-negative bacteria. This enzyme has not been extensively exploited as a drug target, possibly due to the difficulty in obtaining one of the substrates, UDP-MurNAc-L-Ala-gamma-D-Glu-meso-diaminopimelate, which is usually purified from bacteria. We have identified putative inhibitors of Escherichia c...
متن کاملSynergistic Effect of 4 Weeks of Endurance Training With Probiotic Supplementation on the Expression of Atrogin-1 and Murf-1 Genes in the Soleus Muscle of Diabetic Rats
Background: One of the most common problems in diabetic patients is muscle atrophy. Therefore, the present study aimed to investigate the synergistic effect of endurance training with probiotic supplementation on Atrogin-1 and MuRF-1 genes gene expression in the soleus muscle of diabetic rats. Methods: In this study, 32 male Wistar rats were randomly divided into one normal control (NC) and fo...
متن کاملEffect of 10 Weeks of High-Intensity Interval Training on Protein Levels of NF-kB and Expression of Atrogin-1 and MuRF-1 in Cardiomyocytes of Female Mice with Breast Cancer
Introduction: Limiting cancer-induced cardiac atrophy is a highly important for improving the survival rates and quality of life in cancer patients. The purpose of this study was to evaluate the effect of 10 weeks of high-intensity interval training (HIIT) on cardiac muscle weight, NF-kB protein expression, and expression of Atrogin-1 and MuRF-1 genes in the heart muscle of breast cancer–bearin...
متن کاملIsolation and Characterization of a New Peroxisome Deficient CHO Mutant Cell Belonging to Complementation Group 12
We searched for novel Chinese hamster ovary (CHO) cell mutants defective in peroxisome biogenesis by an improved method using peroxisome targeting sequence (PTS) of Pex3p (amino acid residues 1–40)-fused enhanced green fluorescent protein (EGFP). From mutagenized TKaEG3(1–40) cells, the wild-type CHO-K1 stably expressing rat Pex2p and of rat Pex3p(1–40)-EGFP, numerous cell colonies resistant to...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
- Journal of bacteriology
دوره 188 7 شماره
صفحات -
تاریخ انتشار 2006