URA5-RFLP is one of the most widely used genotyping methods relating to Cryptococcus neoformans and C. gattii consensus genotype nomenclature. In order to identify a molecular type, this method uses a visual comparison of digested PCR products of tested and reference strains, therefore any anomaly in RFLP patterns of studied isolates makes recognition difficult or impossible. This report describes a strain of VNIV type showing an atypical URA5-RFLP pattern as well as a group of AD hybrids displaying the same anomaly. The atypical RFLP pattern is the result of a point mutation and emergence of a new restriction site. Emergence of the allele presenting a new banding pattern may lead to misidentification using the URA5-RFLP technique; the results of this study as well as the literature data may suggest the spread of the allele in the environment.
- MeSH
- Cryptococcus neoformans klasifikace genetika MeSH
- genotyp MeSH
- geny hub genetika MeSH
- mikrobiologie životního prostředí MeSH
- mutace MeSH
- mykologické určovací techniky MeSH
- orotátfosforibosyltransferasa genetika MeSH
- polymorfismus délky restrikčních fragmentů MeSH
- sekvence nukleotidů MeSH
- Publikační typ
- časopisecké články MeSH
Cryptococcosis is caused by members of the Cryptococcus neoformans/Cryptococcus gattii species complex. Based on molecular identification, these two species have been further differentiated into molecular types. The aim of this work was to characterize clinical cryptococcal isolates recovered from six hospitals in Northeast Mexico from 1995 to 2011. One hundred and sixty-six isolates, which were characterized by biochemical tests and in vitro susceptibility to amphotericin B, fluconazole, and voriconazole, and M13 PCR fingerprinting, were included in this study. Utilizing phenotypic tests, 153 isolates (92.16 %) were identified as C. neoformans and 13 (7.83 %) as C. gattii. All isolates were susceptible to all antifungals tested. Employing M13 PCR fingerprinting, eight molecular types were detected. VNI was the most common genotype (124 cases; 74.6 %), followed by VNII (15 cases; 9 %), VNIII (8 cases; 4.8 %), VNIV (6 cases; 3.6 %), VGI (6 cases; 3.6 %), VGII (3 cases; 1.8 %), and VGIII and VGIV (2 cases, 1.2 % each). We confirm the presence of C. gattii in clinical isolates in Northeast Mexico, and a high clonal diversity in the studied strains of C. neoformans/C. gattii species complex.
- MeSH
- antifungální látky farmakologie MeSH
- Cryptococcus gattii klasifikace genetika izolace a purifikace MeSH
- Cryptococcus neoformans klasifikace genetika izolace a purifikace MeSH
- DNA fingerprinting MeSH
- dospělí MeSH
- kryptokokóza epidemiologie mikrobiologie MeSH
- lidé středního věku MeSH
- lidé MeSH
- mikrobiální testy citlivosti MeSH
- mladiství MeSH
- mladý dospělý MeSH
- molekulární epidemiologie MeSH
- molekulární typizace * MeSH
- mykologické určovací techniky * MeSH
- nemocnice MeSH
- polymerázová řetězová reakce MeSH
- senioři MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mladiství MeSH
- mladý dospělý MeSH
- mužské pohlaví MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Mexiko epidemiologie MeSH
Case of 59-year-old male with chronic obstructive pulmonary disease and a number of comorbidities, who has developed meningoencephalitis caused by Cryptococcus neoformans var. grubii with polyarteritis nodosa diagnosed during hospitalization, was presented. Before evidence of meningoencephalitis, the patient was being treated with ketoconazole and low doses of fluconazole (200 mg/day) for alleged candidiasis. The dosage was increased (800 mg/day) following laboratory diagnosis of C. neoformans based on positive latex agglutination test and biochemical identification of encapsulated yeast isolated from the blood and CSF. Later, the yeast identification was confirmed by sequencing analysis. Owing to inadequate clinical response, fluconazole therapy was switched to voriconazole (400 mg/day) and later to intravenous amphotericin B (1.0 mg/kg per day). Despite of a temporary stabilization and improvement, which correlated with decline of cryptococcal antigen titers (from 1:1024 to 1:8), after 6 weeks, the patient's underlying condition deteriorated due to severe pancolitis and serious nosocomial bacterial infections. The patient died of multiorgan failure several days later. Our case demonstrates a possible connection between the development of life-threatening cryptococcosis and an autoimmune vasculitis disease and emphasizes that the outcome of the management of cryptococcal meningoencephalitis is highly dependent on early diagnosis, adequate treatment, including dosage, and last but not least control of underlying disease and risk factors.
- MeSH
- antifungální látky aplikace a dávkování MeSH
- Cryptococcus neoformans účinky léků genetika izolace a purifikace MeSH
- fatální výsledek MeSH
- flukonazol aplikace a dávkování MeSH
- lidé středního věku MeSH
- lidé MeSH
- meningoencefalitida farmakoterapie etiologie mikrobiologie MeSH
- polyarteritis nodosa komplikace mikrobiologie MeSH
- Check Tag
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- kazuistiky MeSH
- práce podpořená grantem MeSH
AIMS: Limited aeration has been demonstrated to cause slowdown in proliferation and delayed budding, resulting eventually in a unique unbudded G2-arrest in the obligate aerobic pathogenic yeast Cryptococcus neoformans. Also, the ability to adapt to decreased oxygen levels during pathogenesis has been identified as a virulence factor in C. neoformans. The aim of this study was to identify and characterize genes that are necessary for the proliferation slowdown and G2-arrest caused by limited aeration. METHODS: Random mutants were prepared and screened for lack of typical slowdown of proliferation under limited aeration. The CNAG_00156.2 gene coding for a zinc-finger transcription factor was identified in mutants showing most distinctive phenotype. Targeted deletion strain and reconstituted strain were prepared to characterize and confirm the gene functions. This gene was also identified in a parallel studies as homologous both to calcineurin responsive (Crz1) and PKC1-dependent (SP1-like) transcription factors. RESULTS: We have confirmed the role of the cryptococcal homologue of CRZ1/SP1-like transcription factor in cell integrity, and newly demonstrated its role in slowdown of proliferation and survival under reduced aeration, in biofilm formation and in susceptibility to fluconazole. CONCLUSIONS: Our data demonstrate a tight molecular link between slowdown of proliferation during hypoxic adaptation and maintenance of cell integrity in C. neoformans and present a new role for the CRZ1 family of transcription factors in fungi. The exact positioning of this protein in cryptococcal signalling cascades remains to be clarified.
- MeSH
- anaerobióza MeSH
- antifungální látky farmakologie MeSH
- biofilmy růst a vývoj MeSH
- Cryptococcus neoformans účinky léků genetika růst a vývoj MeSH
- delece genu MeSH
- flukonazol farmakologie MeSH
- kontrolní body buněčného cyklu genetika MeSH
- mikrobiální viabilita MeSH
- proteiny Caenorhabditis elegans genetika MeSH
- transkripční faktory genetika MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
