Quantitative Proteomic Analysis of Parental and adh1 Mutant Isolates of Candida albicansin Mature Phase Biofilm

摘要

Our initial results showed that there were 171 spots whose mean intensities were significantly different among the experimental groups and were further investigated as spots of interest. Most of the differential expression was between growth conditions, indicating that formation of biofilm changed the protein profile the most. For instance, MET6 gene product (cobalamin-independent methionine synthase), which has close relationship with biofilm formation, was confirmed to be up-regulated in biofilm product. Also, some glycolytic enzymes such as pyruvate kinase, glucose-6-phosphate isomerase were increased in biofilm group, indicating the role of glycolysis/gluconeogenesis pathways in biofilm formation. Unsupervised principal component analysis (PCA) on expression data resolved the four experimental conditions into three distinct expression groups. As demonstrated by PCA, replicate samples of parental and the adh1 mutant strains from biofilm group were separated clearly while those of the two strains from planktonic group were grouped together. These indicate that the Adh1p plays an role in Candida biofilm formation. The PCA result also showed high reproducibility between the replicate samples but high variability among the experimental groups. Currently, we are in the process of identifying additional altered protein species between groups. These observations will be further investigated and validated with alternative approaches, including pathway analysis, a targeted MRM, or immunoblotting.