RESUMO
Objective To identify and analyze plasma membrane proteins differentially expressed between fluconazole-sensitive and-resistant C.albicans strains.Methods Two C.albicans strains from a same parent,including the fluconazole-sensitive C.albicans strain CA-3 and fluconazole-resistant C.albicans strain CA-16,served as the subject of this study.Plasma membrane proteins were isolated from both of the C.albicans strains,and subjected to two-dimensional polyacrylamide gel electrophoresis analysis for the screening of differentially expressed proteins,which were then identified by using matrix assisted laser desorption/ionization time-of-flight mass spectrometry.The resultant data were searched against a protein database for C.albicans.Results Twentytwo proteins were identified to be differentially expressed between the fiuconazole-resistant and-sensitive C.albicans strain.Of them,6 proteins (Adh1p,Csp37p,Pgk1p,Pgk1p and 2 unnamed proteins,i.e.,gi227305312and gi53954641) were highly expressed,while 16 proteins (Aco1p,Aco1p,Hsp78p,Gut2p,Sdh12p,Ilv2p,Ndh51p,Ndh51p,Atp1p,Pda1p,Srb1p,Idh1p,Tdh1p,Cyt1p,Cox4p,Cox13p) were lowly expressed in the fluconazole-resistant C.albicans strain compared with the fluconazole-sensitive strain.Conclusion The plasma membrane proteins differentially expressed between fluconazole-sensitive and-resistant C.albicans strain are mainly implicated in energy metabolism and mitochondrial function.
RESUMO
Objective To study the effects of tetrandrine on the protein expression profile of C. albicans,and to screen for proteins associated with the effect of tetrandrine. Methods Fluconazole-sensitive C. albicans CA-3 was cultured with or without tetrandrine (250 mg/L) for 6 hours followed by the collection of Candida cells. Total proteins were extracted from these cells and separated by using immobilized pH gradient two-dimensional polyacrylamide gel electrophoresis. Protein spots were detected and analyzed by Image Master 2D Platinum software, and MALDI-TOF/TOF-MS-based method was used to identify these proteins. Results The two-dimensional gel electrophoresis maps of C. albicans proteins before and after the treatment with tetrandrine were successfully obtained with high repeatability. Image analysis revealed a total of 26 differentially expressed protein spots in C. albicans treated with tetrandrine, and 7 differentially expressed proteins were identified by the mass chromatographic analysis, including 1 up-regulated protein (Pst1), and 6 down-regulated proteins (Idh1,Asc1, Rps5, Asn1, Asn1, Srb1 ). Conclusions The expressions of some proteins in fluconazole-sensitive C. albicans experience significant changes after tetrandrine treatment, and Pst1, Idh1, Asc1, Rps5, Asn1, Asn1 and Srb1 may considerab1y contribute to the effects of tetrandrine on C. albicans.
