Oligonucleotide fingerprinting of isolates of Candida species other than C. albicans and of atypical Candida species from human immunodeficiency virus-positive and AIDS patients

Abstract

Oligonucleotide fingerprinting of genomic DNA from oral isolates of four different Candida species other than C. albicans and atypical chlamydospore-positive isolates from human immunodeficiency virus (HIV)-positive individuals and AIDS patients was investigated as a means for differentiating between isolates within individual species. Oligonucleotides composed of simple repetitive sequence motifs, including (GACA)4, (GATA)4, (GGAT)4, (GTG)5, and (GT)8, all yielded fingerprints suitable for strain segregation of 8 C. tropicalis isolates, 12 Torulopsis (Candida) glabrata isolates, 8 atypical Candida isolates, and, except for (GATA)4, 2 C. krusei isolates. This technique makes it possible to carry out sequential hybridization of filter-bound DNA with each probe in turn and so generate several distinct DNA fingerprints of the same DNA sample. However, none of the probes yielded fingerprints suitable for strain segregation with three C. parapsilosis isolates. The (GATA)4 probe was also used to detect restriction fragment length polymorphisms among a genetically closely related group of atypical Candida isolates on primary isolation from an additional HIV-infected patient. These chlamydospore-positive atypical Candida isolates were sucrose positive, were of C. albicans serotype A, hybridized weakly with the C. albicans-specific mid-repeat sequence probe 27A, and yielded fingerprint profiles by random polymorphic DNA analysis that were distinct from those derived from C. albicans isolates. The C. stellatoidea ex-type strain NCPF 3108 was indistinguishable from the atypical Candida isolates in all these tests and also yielded an identical carbohydrate and nitrogen source assimilation profile by using the ID 32C yeast identification system.

Oral candidal carriage and infection in insulin‐treated diabetic patients

“…Of particular interest to this study was the recovery of a number of atypical candidal isolates, with properties consistent with the recently described C. dubliniensis recovered from HIV seropositive and seronegative individuals [17]. This is the ®rst reported ®nding of this species in an insulin-treated DM population.…”

Techniques for investigation of an apparent outbreak of infections with Candida glabrata

“…The simple repeat sequence poly(dG-dT) has been used as a probe to differentiate strains of C. albicans (20), and in this study of C. glabrata, it was used to detect seven patterns from 13 patients. Sullivan et al (18) tested a selection of simple repeat oligonucleotide probes for the differentiation of 12 C. glabrata isolates and described (G-T) 8 as being the most informative, providing four patterns.…”

Difference in virulence between fluconazole‐susceptible and fluconazole‐resistant Candida albicans in a mouse model

“…5 In this study, genotyping of both isolates was performed by arbitrarily primed PCR (AP-PCR) using random 10-mer primer RP02 5¢GCGATCCCCA3¢ as described previously. 10 The amplified DNA was electrophoresed through a 1.2% agarose gel for 2 h at 50 V. DNA molecular size marker IV (Boehringer, Mannheim, Germany) was included. In addition, CARE-2 hybridisation of both isolates was performed as described previously.…”