Mittmann K, Jaquet K, Heilmeyer L M
Institut für Physiologische Chemie, Abteilung für Biochemie Supramolekularer Systeme, Ruhr-Universität Bochum, FRG.
FEBS Lett. 1990 Oct 29;273(1-2):41-5. doi: 10.1016/0014-5793(90)81046-q.
From rabbit and human cardiac troponin I N-terminal mono and bisphosphorylated peptides were isolated which were obtained from Lys-C proteinase digests. Two adjacent phosphoserine residues could be localized in each phosphopeptide following further tryptic digestion. The previously published sequence of rabbit cardiac troponin I had to be corrected. Two adjacent phosphoserine residues are a common motif in the very similar sequences of bovine, rabbit and human cardiac troponin I. The N-terminal sequences are: AcADRSGGSTAG DTVPAPPPVR RRS(P)S(P)ANYRAY ATEPHAK (bovine), AcADESTDA-AG EARPAPAPVR RRS(P)S(P)ANYRAY ATEPHAK (rabbit), (Ac,A,D/N,G,S,S,D/N,A,A,R) EPRPAPAPIR RRS(P)S(P)-NYRAY ATEPHAK (human).
从兔和人心脏肌钙蛋白I中分离出了通过赖氨酰-C蛋白酶消化获得的N端单磷酸化和双磷酸化肽段。经过进一步的胰蛋白酶消化后,可在每个磷酸肽中定位两个相邻的磷酸丝氨酸残基。先前发表的兔心脏肌钙蛋白I序列必须加以修正。在牛、兔和人心脏肌钙蛋白I非常相似的序列中,两个相邻的磷酸丝氨酸残基是一个共同基序。其N端序列如下:乙酰基-ADRSGGSTAG DTVPAPPPVR RRS(P)S(P)ANYRAY ATEPHAK(牛),乙酰基-ADESTDA-AG EARPAPAPVR RRS(P)S(P)ANYRAY ATEPHAK(兔),(乙酰基,A,D/N,G,S,S,D/N,A,A,R)EPRPAPAPIR RRS(P)S(P)-NYRAY ATEPHAK(人)。