Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0848332 (Spots)
 453 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The Bacillus subtilis mutant cal1 carries a non-reverting mutation in ribosomal protein L17 (r-protein L17) that causes both resistance to the antibiotic chalcomycin (Calr) and temperature-sensitive sporulation (Spots). Second-site suppressor (rev) mutations that relieve the Spots phenotype have been isolated from cal1. Three suppressor mutations - rev4, rev10, rev11 - each increase the sporulation frequency of cal1 at the non-permissive temperature from 3% to 95% of the wild-type level. The cal1 rev strains remain resistant to chalcomycin and two-dimensional gel electrophoresis analysis indicates that they contain the same altered r-protein L17 as the original cal1 strain and no additional altered r-proteins. The three rev mutations have been mapped at a single locus between narA and sacA on the B. subtilis chromosome and recombination indexes for the rev mutations indicate that they are tightly linked to one another. Antibiotic resistance Spots mutations that cause temperature-sensitive sporulation have previously been isolated in RNA polymerase, in the 30S and 50S subunits of the ribosome, and in elongation factor G. The rev4, 10, and 11 suppressor mutations are non-specific in their action in that they restore significant levels of sporulation at the non-permissive temperature in all of the Spots strains that we have tested. This result suggests that Spots mutations in components of the B. subtilis transcription and translation systems share a common molecular basis for their sporulation-defective phenotypes.
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PMID:Intergenic suppressors of temperature-sensitive sporulation in Bacillus subtilis are allele non-specific. 680 27

Mutants of Bacillus subtilis resistant to various macrolide antibiotics have been isolated and characterized with respect to their sporulation phenotype and the electrophoretic mobility of their ribosomal proteins (r-proteins). Two types of major alterations of r-protein L17, one probably due to a small deletion, are found among mutants exhibiting high-level macrolide resistance. These mutants are all temperature-sensitive for sporulation (Spots). Low-level resistance to some macrolides is found to be associated with minor alterations in r-protein L17. These mutations do not cause a defective sporulation phenotype. All of the macrolide resistance mutations map at the same locus within the Str-Spc region of the B. subtilis chromosome. Hence, changes in a single ribosomal protein can result in different sporulation phenotypes. Mutants resistant to the aminoglycoside antibiotics neomycin and kanamycin have been isolated. Approximately 5% of these are Spots. Representative mutations, neo162 and kan25, cause concomitant drug resistance and sporulation temperature-sensitivity and map a single-site lesions in the Str-Spc region of the chromosome. Strains bearing neo162 or kan25 are equally cross-resistant to streptomycin or spectinomycin. These mutations define a new B. subtilis drug resistance locus at which mutation can cause defective sporulation.
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PMID:Macrolide and aminoglycoside antibiotic resistance mutations in the bacillus subtilis ribosome resulting in temperature-sensitive sporulation. 680 28