Systematic identification of substrates for profiling of secreted proteases from Aspergillus species.
Reliable and early diagnosis of life-threatening invasive mycoses in neutropenic patients caused by fungi of the Aspergillus species remains challenging because current clinical diagnostic tools lack in sensitivity and/or specificity. During invasive growth a variety of fungal proteases are secreted into the bloodstream and protease profiling with reporter peptides might improve diagnosis of invasive aspergillosis in serum specimens. To characterise the specific protease activity of Aspergillus fumigatus and Aspergillus niger we analyzed Aspergillus culture supernatants, human serum and the mixture of both. A systematic screening for optimised protease substrates was performed using a random peptide library consisting of 360 synthetic peptides featuring fluorescence resonance energy transfer (FRET). We could identify numerous peptides that are selectively cleaved by fungus-specific proteases. These reporter peptides might be feasible for future protease profiling of serum specimens to improve diagnosis and monitoring of invasive aspergillosis.
Schaal
René
R
Institute for Clinical Chemistry, Medical Faculty Mannheim of the University of Heidelberg, University Hospital Mannheim, Theodor-Kutzer-Ufer 1-3, D-68167 Mannheim, Germany.
Kupfahl
Claudio
C
Buchheidt
Dieter
D
Neumaier
Michael
M
Findeisen
Peter
P
D001228:Aspergillosis / Q000175:diagnosis; D001232:Aspergillus fumigatus / Q000201:enzymology*; D001234:Aspergillus niger / Q000201:enzymology*; D003470:Culture Media / Q000737:chemistry; D031541:Fluorescence Resonance Energy Transfer; D005656:Fungal Proteins / Q000097:blood / Q000378:metabolism*; D006801:Humans; D010447:Peptide Hydrolases / Q000378:metabolism*; D010455:Peptides / Q000378:metabolism*; D044967:Serum / Q000737:chemistry
D003470:Culture Media; D005656:Fungal Proteins; D010455:Peptides; D010447:Peptide Hydrolases