[16] Heme-deficient mutants of Staphylococcus aureus

摘要: Publisher Summary This chapter discusses heme-deficient (hem) mutants of facultative fermentative bacteria that are convenient tools to manipulate cytochrome synthesis and cytochrome-linked electron transport systems. Mutants with defects in the respiratory system readily isolable based on resistance antibiotics—in particular, aminoglycosides. Respiratory can be distinguished from normal phenotype by their inability grow nonfermentable substrates small colonies fermentable energy sources. The staphylococcal unusual ability respond low concentrations heroin. Hem other gram-positive gram-negative organisms fail either hemin or require high concentrations. Failure use restricts isolation hem auxotrophs. With exception δ-aminolevulinate (ALA), intermediates biosynthetic pathway unstable impermeable most cells. It reviews a hemin-permeable mutant Escherichia coli has been reported, this may extend range available for biochemical genetic analysis. Mutant strains E. Salmonella typhimurium being exploited studies, they have characterized mainly form cytochromes when grown ALA accumulation porphobilinogen (PBG) porphyrins ALA. Hemin is not effective cells, but it restores b-type activity membrane preparations, provided ATP present.