CHARACTERIZATION OF GENETICALLY DISTINCT SUBGROUP OF CANDIDA-ALBICANSSTRAINS ISOLATED FROM ORAL CAVITIES OF PATIENTS INFECTED WITH HUMAN-IMMUNODEFICIENCY-VIRUS
M. Mccullough et al., CHARACTERIZATION OF GENETICALLY DISTINCT SUBGROUP OF CANDIDA-ALBICANSSTRAINS ISOLATED FROM ORAL CAVITIES OF PATIENTS INFECTED WITH HUMAN-IMMUNODEFICIENCY-VIRUS, Journal of clinical microbiology, 33(3), 1995, pp. 696-700
During the course of a study of oral Candida albicans strains from 60
human immunodeficiency virus-infected patients over a 2.5-year period,
18 of the 295 C. albicans isolates had genomes that failed to hybridi
ze with a C. albicans-specific DNA probe (27A). These strains were ger
m tube positive and chlamydospore positive and were identified as C. a
lbicans by the ID 32C test (API Systems, Montlieu, France). These stra
ins were analyzed for the presence of two other C. albicans-specific D
NA segments by PCR. The first was a C. albicans 1,348-bp species-speci
fic sequence, and the second was a 1,059-bp C. albicans repetitive ele
ment, The probe 27A-hybridizing strains yielded PCR products which dif
fered from those of the nonhybridizing strains. Five of these genetica
lly atypical C. albicans strains and 98 of the C. albicans strains wer
e then analyzed for purported virulence factors. The genetically atypi
cal C. albicans strains, in comparison with typical C. albicans strain
s, produced greater amounts of extracellular proteinase (P = 0.038, St
udent's t test), adhered to a greater degree to buccal epithelial cell
s (P = 0.018, Student's t test), and were less susceptible to the anti
fungal drug 5-flucytosine (P = 0.0003, Mann-Whitney test). Analysis of
these strains with other common antifungal drugs showed no statistica
lly significant variation in susceptibility. The results of this study
indicated that these genetically atypical C. albicans strains possess
increased virulence in comparison with typical C. albicans strains.