• Journal of Microbiology
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• v.40 no.2
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• pp.166-169
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• 2002

Twenty strains of Cryptococcus neoformams isolated from environmental and clinical sources in Korea were examined for their serotypes. Two environmental isolates from pigeon excreta belonged to C. neoformans var. neoformans serotypes A. Of the 18 isolates from clinical specimens, 17 belonged to C. neoformans vats, neoiomans (serotype A : 16, serotype D : 1) and one belonged to C. neoformans vats, gattii serotype B, which was culturally unusual, producing mucous colonies. This is the first report of the identification of C. neoformans roar, gattii serotype B from a patient in Korea.

• Mycobiology
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• v.43 no.3
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• pp.360-365
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• 2015

Multilocus sequence typing analysis was applied to determine the genotypes of 147 (137 clinical and 10 environmental) Cryptococcus neoformans and three clinical Cryptococcus gattii isolates from 1993 to 2014 in Korea. Among the 137 clinical isolates of C. neoformans, the most prevalent genotype was ST5 (n = 131), followed by ST31 (n = 5) and ST127 (n = 1). Three C. gattii strains were identified as ST57, ST7, and ST113. All environmental isolates were identified as C. neoformans with two genotypes, ST5 (n = 7) and ST31 (n = 3). Our results show that C. neoformans isolates in Korea are genetically homogeneous, and represent a close genetic relationship between clinical and environmental isolates.

• Mycobiology
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• v.31 no.3
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• pp.162-165
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• 2003

Three hundred and sixty five samples of avian droppings, collected from parks and zoo, were investigated for the occurrence of Cryptococcus neoformans in Korea. Thirteen samples were positive for C. neoformans. All isolates were obtained from withered pigeon droppings. Identification and serotyping of isolates were determined by means of serological test and polymerase chain reaction(PCR) fingerprinting. All isolates belonged to C. neoformans var. grubbi(serotype A).

• Journal of Microbiology
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• v.43 no.5
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• pp.469-472
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• 2005

Seventy-two pigeon dropping samples were collected from 26 different localities in Seoul and investigated for the occurrence of Cryptococcus neoformans. Seventeen samples from 8 different localities were found to be positive for C. neoformans. All isolates were obtained from withered pigeon droppings. Identification and serotyping of the isolates were determined by means of serological testing and DNA fingerprinting. All isolates belonged to C. neoformans var. grubbi (serotype A).

• Mycobiology
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• v.30 no.2
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• pp.93-95
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• 2002

The antifungal activities of propolis on Cryptococcus neoformans and Candida albicans were evaluated. In microbroth culture assay, the MIC(minimum inhibitory concentration) of propolis for C. neoformans and C. albicans were 2 and 16 mg/ml, respectively. In propolis-included solid medium assay, the MIC of propolis for C. neoformans and C. albicans were 4 and 16 mg/ml, respectively. Propolis showed fungicidal activity against C. neoformans, whereas propolis possesed fungistatic activity against C. albicans. The MFC(minimum fungicidal concentration) for C. neoformans was 8 mg/ml. Cell morphology of C. neoformans was affected by treatment of propolis. In scanning electron microscope, the appearance of cell rupture was observed.

• Applied Microscopy
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• v.23 no.2
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• pp.97-106
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• 1993

This study was done to elucidate the electron microscopic characteristics of certain pathogenic fungi. Four Candida species, (C. albicans, C. tropicalis, C. parapsilosis and C. glabrate) and Cryptococcus neoformans were cultured for 3 days at $30^{\circ}C$ in the Sabouraud dextrose medium. After incubation, they were stored at $4^{\circ}C$ for 24hours. Fine structures were analyzed by morphometry, and Tukey's HSD test was used for statistics. On scanning electron microscopy C. albicans and C. neoformans were similar in size but different in shape, showing sphero-shape or ovalo-shape in C. neoformans. Surface of C. neoformans was coarse and spiny, but Candida species examined were uniformly smooth. In size, C. glabrata was the smallest among them. Budding scar as seen on the surface of Candida species by the number ranging from 1 to 7. Cryptococcus neoformans showed one or two budding scar. On transmission electron microscopy the cytoplasm of most yeast cells showed plentiful glycogen particles, mitochondria, peroxisomes and vacuoles. However, cell walls were different among four Candida species and Cryptococcus neoformans. The cell wall of Candida species consisted of fibrous layer, that was electron dense layer and transparent layer, in contrast to Cryptococcus neoformans consisted of electron dense layer with lamellar structure. This layer was two times thicker than that of Candida species. The outer layer of cell wall was of radiating pattern.

• Mycobiology
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• v.33 no.4
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• pp.188-193
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• 2005

Twenty nine samples of pigeon droppings (n = 12) and soil contaminated with avian excreta (n = 19), collected from different sites in Busan, were examined for isolation and characterization of Cryptococcus neoformans. Of these samples, 5 strains of C. neoformans were recovered from pigeon droppings (5/12 : 41.7%). All isolates were belonged to C. neoformans var. grubii (serotype A). The extracellular enzyme activities of the strains by using the API-ZYM system showed two different enzymatic patterns. The genetic variability among C. neoformans isolates was analyzed by random amplified polymorphic DNA (RAPD) using three 10-mer primers. Two different RAPD patterns, which clearly distinguished the isolates, were identified. Analysis of RAPD patterns provided a good characterization of environmental strains of C. neoformans serotype A as a heterogeneous group and were in good agreement with enzymatic profiles.

• Korean Journal of Microbiology
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• v.52 no.2
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• pp.226-229
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• 2016

The growth of two different fungal species, human pathogenic Cryptococcus neoformans and plant pathogenic Alternaria alternata were inhibited by a chitinase (Chi2) expressed in the autolysing tissue of Coprinellus congregatus. The cell wall thickness was reduced (up to 32%) in C. neoformans compared with that of normal cell, and polysaccharide fibers located outside of the cell wall were also severely removed. The hyphal growth of A. alternata on agar plate was stopped by the enzyme. The allergic inflammation induced by A. alternata was reduced by the enzyme reaction when compared with untreated control in a mouse model.

• Journal of Veterinary Clinics
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• v.13 no.2
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• pp.198-203
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• 1996

일반적인 치료에 반응을 나타내지 않는 호흡곤란증에 걸린 4년령의 Shepherd개에서 피부, 눈, 림프절의 병변을 동반한 치명적인 파종성 크립토콕스병이 진단되었다. 세포학적검사에 의해 난원형 내지 구형이고, 두꺼운 협막을 갖고 있는, 형태학적으로 Cryptococcus neoformans와 일치하는 효모균이 증명되었다. 이 병원체는 혈액, 오줌, 콧물, 견갑전림프절 흡인물, 피부생검 시료, 피부 면봉 시료 등을 25$\circ $C의 Pal씨 배지에 접종하여 용이하게 분리되었다 배양물을 PHOL염색액으로 염색하여 현미경으로 검사한 결과 얇은 막에 싸인 발아를 나타내거나. 나타내지 않는 구형 내지 난원형의 효모균이 증명되었다. 이 개는 ketaconazole 로 치료를 시작 한 후 6일만에 폐사하였다. 공기, 흙, 비둘기 배설물, 톱밥 등을 Pal씨 배지에 접종하여 C.neoformans가 배양됨으로써 역학적으로 환경이 병원소 역할을 한 것으로 판단되었다. 환축과 환경으로부터 분리된 균주는 세밀한 동정결과 neoformans (serotype AD)에 속하며, Filobasidiella neoformans "alpha" mating type을 나타내었다. 이 연구결과, Pal씨 배지가 크립토콕스병의 조기진단과 역학적 조사에 훌륭한 감별배지라는 것이 입증되었다. 개량된 Pal씨 배지는 C. neoformans의 genetic crossing을 판단하는데 성공적으로 사용할 수 있었다.

• Mycobiology
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• v.38 no.3
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• pp.215-218
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• 2010

Azoles are currently the most widely used class of antifungal drugs clinically, and are effective for treating fungal infections. Target site of azoles is ergosterol biosynthesis in fungal cell membrane, which is absent in the mammalian host. However, the development of resistance to azole treatments in the fungal pathogen has become a significant challenge. Here, we report the identification and functional characterization of a UPC2 homolog in the human pathogen Cryptococcus neoformans. UPC2 plays roles in ergosterol biosynthesis, which is also affected by the availability of iron in Saccharomyces cerevisiae and Candida albicans. C. neoformans mutants lacking UPC2 were constructed, and a number of phenotypic characteristics, including antifungal susceptibility and iron utilization, were analyzed. No differences were found between the mutant phenotypes and wild type, suggesting that the role of C. neoformans UPC2 homolog may be different from those in S. cerevisiae and C. albicans, and that the gene may have a yet unknown function.