Related Experiment Video
Updated: Jul 16, 2026
Assay for Adhesion and Agar Invasion in S. cerevisiae
Published on: November 8, 2006
Differentially expressed proteins of pathogenic Penicillium marneffei in yeast and mycelial phases
Liyan Xi1, Xiaorong Xu1, Wei Liu2
1Department of Dermatology, Second Affiliated Hospital, Sun Yat-Sen University, 107 West Yanjiang Road, Guangzhou 510120, China.
Abstract:
Penicillium marneffei is a dimorphic fungus endemic in southeast Asia. The incidence of P. marneffei infection has increased greatly in this region with the spread of human immunodeficiency virus, but the infection routes and pathogenic mechanisms of P. marneffei remain poorly understood. P. marneffei is an opportunistic human pathogen exhibiting a temperature-dependent dimorphic switch. At 25 degrees C it grows as filamentous hyphae, whilst at 37 degrees C it forms uninucleate yeast cells and divides by fission. Dimorphic fungal pathogenicity is frequently associated with the dimorphic switch, but the mechanism that regulates the switch has remained obscure. In this report, two-dimensional difference gel electrophoresis was used to investigate the proteins expressed differentially in the yeast and mycelial phases of a wild-type isolate of P. marneffei. Among thousands of protein molecules displayed, more than 500 showed differential expression between the two phases. In particular, 26 proteins were identified using matrix-assisted laser desorption/ionization time-of-flight MS. Expression of catalase-peroxidase, isocitrate lyase, Hsp90, binding protein and cytochrome P-450 increased significantly in the yeast phase, whereas levels of poly(A) polymerase and SNF22 were reduced.
Insights
Penicillium marneffei, a fungus causing infections in Southeast Asia, switches between yeast and hyphal forms. This study identified over 500 differentially expressed proteins, revealing key molecular changes during this dimorphic transition.
Area of Science:
- Mycology
- Medical Mycology
- Molecular Biology
Background:
- Penicillium marneffei is a dimorphic fungus endemic to Southeast Asia.
- Infections are increasing, particularly in individuals with human immunodeficiency virus.
- The infection routes and pathogenic mechanisms remain poorly understood.
- The temperature-dependent dimorphic switch (hyphae at 25°C, yeast at 37°C) is crucial for pathogenicity but its regulation is obscure.
Purpose of the Study:
- To investigate the proteomic differences between the yeast and mycelial phases of Penicillium marneffei.
- To identify proteins involved in the dimorphic transition.
Main Methods:
- Two-dimensional difference gel electrophoresis (2D-DIGE) was employed to compare protein expression profiles.
- Proteins showing differential expression were identified using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS).
Main Results:
- Over 500 proteins exhibited differential expression between the yeast and mycelial phases.
- Twenty-six proteins were successfully identified.
- Key proteins like catalase-peroxidase, isocitrate lyase, Hsp90, binding protein, and cytochrome P-450 showed increased expression in the yeast phase.
- Conversely, poly(A) polymerase and SNF22 levels were reduced in the yeast phase.
Conclusions:
- The study provides a proteomic landscape of Penicillium marneffei's dimorphic transition.
- Identified proteins offer insights into the molecular mechanisms regulating the switch between fungal forms.
- Understanding these mechanisms could lead to novel therapeutic strategies against P. marneffei infections.
