Grigoriants O O, Desiderio D M
Charles B. Stout Neuroscience Mass Spectrometry Laboratory, The University of Tennessee, Memphis, USA.
Int J Pept Protein Res. 1996 Jan-Feb;47(1-2):123-30.
Mass spectrometry was used to determine the molecular mass of rat pituitary beta-endorphin1-31 (BErat, 1-31). The measured molecular mass (3435 +/- 1 Da, n = 5) of endogenous BErat, 1-31 differed from the molecular mass of commercially available synthetic BErat, 1-31 (3465 +/- 1 Da, n = 9), but corresponded to the molecular mass of synthetic BEbovine, 1-31 (3436 +/- 3 Da, n = 3). Based on the combination of these ESIMS molecular mass measurements, HPLC retention time data, LSIMS measurement of the molecular mass of selected tryptic fragments, and consideration of codon sequences, we suggest that the amino-acid sequence of endogenous BErat, 1-31 differs from the DNA-deduced sequence of BErat, 1-31, and that endogenous BErat, 1-31 contains Ala instead of Val in position 26.
采用质谱分析法测定大鼠垂体β-内啡肽1-31（BErat, 1-31）的分子量。内源性BErat, 1-31的测定分子量（3435±1 Da，n = 5）与市售合成BErat, 1-31的分子量（3465±1 Da，n = 9）不同，但与合成牛β-内啡肽1-31（3436±3 Da，n = 3）的分子量一致。基于这些电喷雾离子化质谱（ESIMS）分子量测量结果、高效液相色谱（HPLC）保留时间数据、所选胰蛋白酶片段分子量的液相二次离子质谱（LSIMS）测量结果以及密码子序列的考虑，我们认为内源性BErat, 1-31的氨基酸序列与BErat, 1-31的DNA推导序列不同，且内源性BErat, 1-31在第26位含有丙氨酸而非缬氨酸。
