Sundari C Sivakama, Chakraborty K, Nagaraj R, Jagannadham M V
Centre for Cellular and Molecular Biology, Council of Scientific and Industrial Research, Uppal Road, Hyderabad-500 007, India.
Protein Pept Lett. 2010 Feb;17(2):168-71. doi: 10.2174/092986610790225969.
Tert- butylation of tryptophan (2', 5', 7'- tri tertiary butyl tryptophan), formed during acidolytic cleavage of synthetic peptides Ac-KLVYWAE-CONH(2) (A-YW) and Ac-KLVWWAE-CONH(2) (A-WW), that are analogs of the fragment of Alzheimer's beta-amyloid peptide Ac-KLVFFAE-CONH(2), during solid-phase peptide synthesis, was characterized by matrix-assisted laser desorption/ionization time of flight/time of flight (MALDI TOF/TOF) mass spectrometry. Crude peptide was fractionated by high performance liquid chromatography. Peptide fractions were sequenced and modified tryptophan was determined with the help of MALDI TOF/TOF mass spectra. Thus, it is possible to pinpoint the particular tryptophan residue that undergoes modification during synthesis of peptides containing multiple tryptophan residues.
在固相肽合成过程中，对合成肽Ac-KLVYWAE-CONH₂（A-YW）和Ac-KLVWWAE-CONH₂（A-WW）（它们是阿尔茨海默病β-淀粉样肽片段Ac-KLVFFAE-CONH₂的类似物）进行酸解切割时形成的色氨酸叔丁基化产物（2', 5', 7'-三叔丁基色氨酸），通过基质辅助激光解吸/电离飞行时间/飞行时间（MALDI TOF/TOF）质谱进行了表征。粗肽通过高效液相色谱进行分离。对肽馏分进行测序，并借助MALDI TOF/TOF质谱确定修饰的色氨酸。因此，有可能精确找出在含有多个色氨酸残基的肽合成过程中发生修饰的特定色氨酸残基。
