title: Altered hemolysin production in urine-grown uroisolates of Escherichia coli.
abstract: Fifteen uroisolates of E. coli were studied for both cell-free and cell-bound hemolysin production. Estimations were done in Trypticase soy broth (TSB, providing iron-replete medium) TSB + 2,2'-bipyridine (providing experimentally created iron-depleted conditions) and pooled normal human urine (providing natural iron-depleted growth medium). In TSB 40% of strains showed no detectable cell-free hemolysin, they were able to produce it in the presence of 2,2'-bipyridine and more so when grown in urine. The cell-bound hemolysin was produced by all the strains in TSB, but in the presence of 2,2'-bipyridine and urine an insignificant increase was observed. All the strains when given 2nd and 3rd passage in urine, were found to elaborate significantly more cell-free as well as cell-bound hemolysin.
authors.affiliation: Department of Microbiology, Panjab University, Chandigarh, India.
authors.forename: R
authors.initials: R
authors.lastname: Mittal
authors.forename: S
authors.initials: S
authors.lastname: Sharma
mesh_terms: D001426:Bacterial Proteins / Q000096:biosynthesis*; D003470:Culture Media; D004926:Escherichia coli / Q000254:growth & development / Q000302:isolation & purification / Q000378:metabolism*; D029968:Escherichia coli Proteins; D006460:Hemolysin Proteins / Q000096:biosynthesis*; D006801:Humans; D014556:Urine
chemical_list: D001426:Bacterial Proteins; D003470:Culture Media; D029968:Escherichia coli Proteins; D006460:Hemolysin Proteins; C036507:Hlya protein, E coli