Phenotypic characterization and virulence of two white nonsporulating Aspergillus fumigatus isolates

Abstract

Abstract:

Objective In this study, another white nonsporulating A.fumigatus strain (named as A2j) was compared with reported nonsporulating strain A1j in terms of morphology and virulence.Methods A2j was confirmed by DNA sequencing of internal transcribed spacer (ITS) regions and partialb-tubulin genes.We incubated A1j and A2j through the slide culture method to compare them under a microscope.We observe the morphology of A1j and A2j at different times or on various medium types.An immunosuppressed mice model was created to compare the virulence of A1j, A2j and Af293.Results A2j was accurately identified as A.fumigatus by ITS and β-tubulin sequencing.Both A1j and A2j showed abnormal germination under the microscope compared to those of the reference strain Af293 by the slide culture method.Neither increased time nor different medium types could stimulate the formation of spores and pigment.A1j cannot grow and A2j can grow at 50℃.A1j is hypovirulentin immunosuppressed mice model;however, A2j is virulent compared to the standard strain Af293.Conclusion The newly A.fumigatus A2j and A1j have significant differences in growth rate, thermotolerance and virulence.

Key words: Aspergillus fumigatus, Identification, Sporulation, Invasive aspergillosis model

CLC Number:

R379.6

JIANG Yuan, ZHANG Cai-yun, WANG Feng-yuan, KONG Qing-tao, ZHANG Zheng, ZENG Qiu-qiong, LONG Nan-biao, SANG Hong. Phenotypic characterization and virulence of two white nonsporulating Aspergillus fumigatus isolates[J]. Chinese Journal of Mycology, 2017, 12(2): 69-73.

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