Department of Biochemistry, Duke University Medical Center, Durham, NC 27710, USA.
Anal Biochem. 2011 Feb 15;409(2):284-9. doi: 10.1016/j.ab.2010.10.035. Epub 2010 Nov 2.
Two homologous 29 amino acid-long highly hydrophobic membrane miniproteins were identified in the Bligh-Dyer lipid extracts of Escherichia coli and Salmonella typhimurium using liquid chromatography/tandem mass spectrometry (LC/MS/MS). The amino acid sequences of the proteins were determined by collision-induced dissociation tandem mass spectrometry, in conjunction with a translating BLAST (tBLASTn) search, i.e., comparing the MS/MS-determined protein query sequence against the six-frame translations of the nucleotide sequences of the E. coli and S. typhimurium genomes. Further MS characterization revealed that both proteins retain the N-terminal initiating formyl-methionines. The methodologies described here may be amendable for detecting and characterizing small hydrophobic proteins in other organisms that are difficult to annotate or analyze by conventional methods.
使用液相色谱/串联质谱（LC/MS/MS）技术，从大肠杆菌和鼠伤寒沙门氏菌的布莱尔-戴尔脂质提取物中鉴定出两种同源的 29 个氨基酸长的高度疏水性膜微蛋白。通过碰撞诱导解离串联质谱，结合翻译 BLAST（tBLASTn）搜索，即比较 MS/MS 确定的蛋白查询序列与大肠杆菌和鼠伤寒沙门氏菌基因组的六框翻译核苷酸序列，确定了这些蛋白的氨基酸序列。进一步的 MS 特征分析表明，这两种蛋白都保留了 N 端起始的甲酰甲硫氨酸。这里描述的方法可能适用于检测和表征其他难以通过传统方法进行注释或分析的生物体中的小型疏水性蛋白。
