CONTRIBUTION TO THE KNOWLEDGE OF THE ENZYMATIC-ACTIVITY OF YEASTS OF CLINICAL INTEREST

The determination of the enzymatic activity of the yeasts has been app lied to the identification of species, specially that of Candida albic ans. In order to know its usefulness in species of clinical interest, we have tested the commercial system API ZYM (Bio Merieux) on 500 isol ated strains of different organic samples, belonging to eight genera a nd twenty species. All the strains showed positivity to Phosphatase al caline, Esterase (C4), Esterase lipase (C8), Leucine arylamidase and P hosphatase acid, and negativity to Lipase (C14), Trypsin, Chymotrypsin , alpha-galactosidase, beta-glucoronidase, alpha-manosidase and alpha- fucosidase. Fourteen enzymatic activity patterns were obtained conside ring the substrates with variable results for the whole of the strains : Valine arylamidase, Cystine arylamidase, Naphthol-AS-BI-phosphohydro lase, beta-galactosidase, alpha-glucosidase, beta-glucosidase and N-ac etyl-beta-glucosaminidase. In the majority of the species, the enzymat ic profile did not have very specific results since it is usually shar ed by more than one species. C. albicans is that which presents the gr eatest number of enzymatic variations, some of these are similar to th ose of other common clinical species, such as Candida krusei, Candida parapsilosis and Candida tropicalis. This system is proposed as a rapi d method for identification and as an epidemiological marker of medica lly important yeasts.