Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 4 de 4
Filter
Add more filters










Database
Language
Publication year range
1.
J Clin Microbiol ; 39(4): 1396-401, 2001 Apr.
Article in English | MEDLINE | ID: mdl-11283062

ABSTRACT

Phospholipase C plays a key role in the pathogenesis of several bacterial infections, for example, those caused by Clostridium perfringens and Listeria monocytogenes. Previous studies have reported multiple copies of plc genes homologous to Pseudomonas aeruginosa plcH and plcN genes encoding the hemolytic and nonhemolytic phospholipase C enzymes in the genomes of Mycobacterium tuberculosis, M. marinum, M. bovis, and M. ulcerans. In this study we analyzed the possible relationship between phospholipase C and hemolytic activity in 21 strains of nontuberculous mycobacteria representing nine different species. Detection of phospholipase C enzymatic activity was carried out using thin-layer chromatography to detect diglycerides in the hydrolysates of radiolabeled phosphatidylcholine. DNA sequences of M. kansasii and M. marinum homologous to the genes encoding phospholipase C from M. tuberculosis and M. ulcerans were identified by DNA-DNA hybridization and sequencing. Finally, we developed a direct and simple assay to detect mycobacterial hemolytic activity. This assay is based on a modified blood agar medium that allows the growth and expression of hemolysis of slow-growing mycobacteria. Hemolytic activity was detected in M. avium, M. intracellulare, M. ulcerans, M. marinum, M. tuberculosis, and M. kansasii mycobacteria with phospholipase C activity, but not in M. fortuitum. No hemolytic activity was detected in M. smegmatis, M. gordonae, and M. vaccae. Whether or not phospholipase C enzyme plays a role in the pathogenesis of nontuberculous mycobacterial diseases needs further investigation.


Subject(s)
Hemolysis , Mycobacterium/enzymology , Mycobacterium/pathogenicity , Type C Phospholipases/metabolism , Culture Media , Humans , Mycobacterium Infections/microbiology , Nucleic Acid Hybridization , Phospholipase D/metabolism , Type C Phospholipases/genetics
3.
Infect Immun ; 68(5): 2995-7, 2000 May.
Article in English | MEDLINE | ID: mdl-10769001

ABSTRACT

This study reports the existence of phospholipase C and D enzymatic activities in Mycobacterium ulcerans cultures as determined by use of thin-layer chromatography to detect diglycerides in hydrolysates of radiolabeled phosphatidylcholine. M. ulcerans DNA sequences homologous to the genes encoding phospholipase C in Mycobacterium tuberculosis and Pseudomonas aeruginosa were identified by sequence analysis and DNA-DNA hybridization. Whether or not the phospholipase C and D enzymes of M. ulcerans plays a role in the pathogenesis of the disease needs further investigation.


Subject(s)
Mycobacterium ulcerans/enzymology , Phospholipase D/metabolism , Type C Phospholipases/metabolism , DNA, Bacterial , Humans , Mycobacterium ulcerans/genetics , Nucleic Acid Hybridization , Polymerase Chain Reaction/methods , Type C Phospholipases/genetics
4.
FEMS Microbiol Lett ; 181(1): 153-7, 1999 Dec 01.
Article in English | MEDLINE | ID: mdl-10564801

ABSTRACT

The pathogenic slow-growing Mycobacterium ulcerans has, until now, been cultured in liquid media containing albumin. Here, we report the first description of use of Sauton medium and modified Reid medium, two protein-free media, in which M. ulcerans was able to grow and produce its toxin, a major virulence factor of this environmental organism which causes a skin disease commonly called Buruli ulcer. These results suggest that Sauton and modified Reid may be useful for certain fields of M. ulcerans research requiring protein-free growth conditions.


Subject(s)
Bacterial Toxins/biosynthesis , Mycobacterium ulcerans/growth & development , Mycobacterium ulcerans/metabolism , Bacterial Toxins/toxicity , Cell Line , Culture Media/chemistry , Humans , Mycobacterium Infections, Nontuberculous/microbiology
SELECTION OF CITATIONS
SEARCH DETAIL
...