L C Wu

Medical University of Ohio at Toledo, Toledo, Ohio, United States

Are you L C Wu?

Claim your profile

Publications (8)30.73 Total impact

  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Clinical isolates of Candida guilliermondii that were investigated by isoenzyme and randomly amplified polymorphic DNA analyses represented two distinct species. The two species were distinguished on the basis of delayed fermentation of galactose. The larger group of isolates was closely related to the anamorph C. guilliermondii ATCC 6260T (T = type strain) and its teleomorph, Yamadazyma (= Pichia) guilliermondii ATCC 46036T. The remaining group, whose members fermented galactose, was very similar to Candida fermentati CBS 2022, which had for many years been placed in synonymy with C. guilliermondii. Three additional groups were represented by individual strains; these strains included C. guilliermondii var. soya ATCC 20216, which was found to represent Yamadazyma ohmeri. The type strain of Y. guilliermondii is redefined.
    International journal of systematic bacteriology 05/1997; 47(2):385-93. · 2.27 Impact Factor
  • S Zeng, L C Wu, P F Lehmann
    [Show abstract] [Hide abstract]
    ABSTRACT: Random amplified polymorphic DNA (RAPD) profiles, obtained when screening culture collection strains of Candida spp., showed several species to be highly heterogeneous. The RAPD-defined groups were as follows: C. catenulata, two groups among five strains; Debaryomyces hansenii (anamorph C. famata), three groups among five strains; C. sake, three groups among three strains; C. intermedia, two groups among two strains; C. rugosa, two groups among three strains and C. parapsilosis, three groups among four strains. The five strains of Issatchenkia orientalis (anamorph C. krusei) belonged to a single RAPD-defined group. The two strains of the teleomorphic yeast Arxiozyma telluris had distinct RAPD profiles but neither resembled profiles of its anamorph, C. pintolopesii. The two varieties of C. pintolopesii had different RAPD profiles. Researchers are cautioned that organisms with the same name may not be closely related.
    Journal of medical and veterinary mycology: bi-monthly publication of the International Society for Human and Animal Mycology 01/1996; 34(4):293-7.
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Three genetically distinct groups of Candida parapsilosis were detected among clinical isolates. These were distinguishable on the basis of isoenzyme profiles and DNA sequences of internally transcribed spacer (ITS) sequences flanking the 5.8S RNA gene. In an investigation of 45 strains, including 32 clinical isolates from Texas, C. parapsilosis group I composed the majority of the common clinical isolates. The type strain of C. parapsilosis was a member of this group. The 10 group II isolates were indistinguishable from group I strains when tested with the API 20C kit. The two group III isolates differed from those in groups I and II by being D-xylitol positive by the API 20C kit; however, isolates in all groups assimilated D-xylitol from broth. Isoenzyme profiles excluded the close relationship of any of these groups to Lodderomyces elongisporus, which is a teleomorphic yeast that has a physiological profile similar to that of C. parapsilosis. Although there were insignificant differences in the ITS2 rDNA sequences, comparisons of the ITS1 sequences revealed several differences. A sequence analysis of ITS1 in which missing bases were counted as mismatches showed the following similarities: group I versus group II, 87.7%; group I versus group III, 82.1%; group II versus group III, 84.5%. Also, the activity of secreted proteinase showed differences among the three groups, with many group I isolates having moderate to high activity. The degree of susceptibility to antifungal agents, amphotericin B, ketoconazole, and 5-fluorocytosine, could not be used to determine an isolate's group.
    Journal of Clinical Microbiology 08/1995; 33(7):1815-21. · 4.07 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Isoenzyme and protein profiles of clinical isolates initially identified as Candida haemulonii demonstrated the presence of two distinct groups. DNA relatedness studies with representative cultures confirmed the presence of two species. Physiological features that can be used to separate two groups within C. haemulonii are reported.
    Journal of Clinical Microbiology 08/1993; 31(7):1683-7. · 4.07 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Candida species are important nosocomial pathogens, particularly in immunocompromised and critically ill patients. A variety of methods have been used to differentiate strains, but an optimal system has not been established. We compared methods for typing a panel of nine related isolates of Candida tropicalis from an outbreak of sternal wound infections as well as four unrelated control isolates of this species. (The genetic relationships of the nine isolates in the panel had been confirmed previously by restriction fragment analysis.) Typing was undertaken without knowledge of an isolate's origin. Karyotyping by contour-clamped homogeneous electric field (CHEF) gel electrophoresis failed to distinguish between outbreak and control isolates. However, when chromosome-sized DNA was digested with SfiI, EagI, SacII, or NaeI and the fragments were separated by CHEF electrophoresis, the outbreak isolates were readily identified. The isoenzyme profiles of the outbreak isolates were identical and were distinctly different from those of the control isolates. While both isoenzyme profiles and the modified CHEF procedure were discriminatory, the latter is recommended as a relatively convenient and reproducible technique for comparison of types of C. tropicalis.
    Clinical Infectious Diseases 04/1993; 16(3):377-83. · 9.37 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Diverse karyotypes were found for Kluyveromyces marxianus var. marxianus (anamorph = Candida kefyr) when analysed by pulsed-field gel electrophoresis. Two classes were discernible. One class was represented by six or seven chromosome-sized bands ranging from 1000 to 2400 kbp, the other by 9–17 bands including both smaller and larger pieces of DNA. The isozyme and protein profiles of K. marxianus var. marxianus were distinct from those of K. lactis. Two strains, originally derived from the same isolate of K. marxianus var. marxianus, showed identical isozyme patterns but slightly differing karyotypes. For identification of K. marxianus var. marxianus, the isozyme profiles provide a more stable character than the electrophoretic karyotypes.
    Mycological Research 08/1992; · 2.81 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Electrophoretic karyotype (EK) patterns, determined by using contour-clamped homogeneous pulsed-field electrophoresis, and isoenzyme (IZ) profiles were evaluated as methods for strain delineation among 35 isolates of Candida lusitaniae recovered from 15 patients. All isolates were identified to the species level by using conventional morphologic and physiologic criteria, and the identification was confirmed by gas-liquid chromatography analysis of the cellular fatty acids. The isolates were then typed without knowledge of the patient source. The IZ profiles showed all isolates to be closely related. Fifteen EK patterns were found; each pattern was restricted to isolates recovered from a single patient. In contrast, on the basis of heterogeneity in phosphatases, beta-glucosidases, esterases, and catalases, 10 IZ profiles were found; 4 were shared by isolates recovered from more than one patient. Multiple isolates from six patients were analyzed, and for each patient, a single EK- and IZ-defined type was found. The types of isolates obtained from two patients, after the emergence of resistance to amphotericin B, remained the same as the types of isolates obtained earlier. The data suggest that a patient becomes colonized by a single strain of C. lusitaniae which may disseminate to multiple sites, that the colonizing strain can persist during the patient's hospitalization, and that it may develop resistance to amphotericin B. Both EK patterns and IZ profiles can be used to delineate strains of C. lusitaniae, but the EK pattern provides more discriminatory power.
    Journal of Clinical Microbiology 03/1992; 30(2):449-54. · 4.07 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Isoenzyme analysis was performed on multiple strains of two commonly used reference cultures of Candida albicans (B311 and NCPF3153). Whereas strains originating from C. albicans B311 showed no variation in isoenzyme profiles, some strains derived from NCPF3153 were identical to B311 strains but others showed variation in their glucose-6-phosphate dehydrogenase isoenzymes. The results are compared with those from previous analyses with these strains and show that C. albicans can undergo genetic alterations during prolonged maintenance in laboratories.
    Journal of Clinical Microbiology 12/1991; 29(11):2623-5. · 4.07 Impact Factor