title: Brachyspira (Serpulina) pilosicoli of human origin interfere with the haemolytic activity and the growth of Staphylococcus aureus beta-toxin producer.
abstract: Brachyspira (Serpulina) pilosicoli related to intestinal spirochaetosis were found to interfere in vitro with the haemolytic activity and the growth of Staphylococcus aureus beta-toxin producer. This interference was clearly appreciated because a reduction of the zone of the staphylococcal beta-toxin activity, the reduction and/or absence of cooperative haemolysis between bacteria, and the growth reduction of S. aureus were observed when B. (S.) pilosicoli were grown 72-96 hours sooner than S. aureus and after the inoculum of the latter the plates were anaerobically incubated for additional 48-72 hours. The phenomenon was more clearly observed when B. (S.) pilosicoli had a concentration of 8x10(6)-8x10(7) CFU/ml and S. aureus at a concentration ranging from 10(7) to 10(1) CFU/ml was inoculated at a distance from the streaks of B. (S.) pilosicoli ranging from 0-10 mm. When B. (S.) pilosicoli and S. aureus were inoculated at the same time and when B. (S.) pilosicoli grew 24-48 hours sooner than S. aureus only a cooperative haemolysis was observed.
authors.affiliation: Department of Pathology and Laboratory Medicine-Section of Microbiology, University of Parma, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Calderaro
authors.forename: G
authors.initials: G
authors.lastname: Dettori
authors.forename: P
authors.initials: P
authors.lastname: Ragni
authors.forename: R
authors.initials: R
authors.lastname: Guegan
authors.forename: M C
authors.initials: MC
authors.lastname: Arcangeletti
authors.forename: M C
authors.initials: MC
authors.lastname: Medici
authors.forename: C
authors.initials: C
authors.lastname: Chezzi
mesh_terms: D000898:Antibiosis / Q000502:physiology*; D001427:Bacterial Toxins / Q000037:antagonists & inhibitors / Q000096:biosynthesis*; D006461:Hemolysis; D006801:Humans; D008826:Microbial Sensitivity Tests; D013144:Spirochaetales / Q000254:growth & development / Q000502:physiology*; D013211:Staphylococcus aureus / Q000254:growth & development / Q000502:physiology*
chemical_list: D001427:Bacterial Toxins