Microwave-assisted enzyme-catalyzed reactions in various solvent systems.
The work describes the accelerated enzymatic digestion of several proteins in various solvent systems under microwave irradiation. The tryptic fragments of the proteins were analyzed by matrix-assisted laser desorption/ionization mass spectrometry. Under the influence of rapid microwave heating, these enzymatic reactions can proceed in a solvent such as chloroform, which, under traditional digestion conditions, renders the enzyme inactive. The digestion efficiencies and sequence coverages were increased when the trypsin digestions occurred in acetonitrile-, methanol- and chloroform-containing solutions that were heated under microwave irradiation for 10 min using a commercial microwave applicator. The percentage of the protein digested under microwave irradiation increased with the relative acetonitrile content, but decreased as the methanol content was increased. These observations suggest that acetonitrile does not deactivate the enzyme during the irradiation period; in contrast, methanol does deactivate it. In all cases, the digestion efficiencies under microwave irradiation exceed those under conventional conditions.
Lin
Shan-Shan
SS
Department of Chemistry, National Dong Hwa University, Hualien, Taiwan.
Wu
Chi-Hong
CH
Sun
Mei-Chuan
MC
Sun
Chung-Ming
CM
Ho
Yen-Peng
YP
D000818:Animals; D002384:Catalysis; D002417:Cattle; D045304:Cytochromes c / Q000737:chemistry; D006736:Horses; D006358:Hot Temperature; D008872:Microwaves; D009113:Muramidase / Q000737:chemistry; D009211:Myoglobin / Q000737:chemistry; D011506:Proteins / Q000737:chemistry*; D012997:Solvents / Q000737:chemistry*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods; D014357:Trypsin / Q000378:metabolism*; D025801:Ubiquitin / Q000737:chemistry
D009211:Myoglobin; D011506:Proteins; D012997:Solvents; D025801:Ubiquitin; D045304:Cytochromes c; D009113:Muramidase; D014357:Trypsin