Shand R F, Miercke L J, Mitra A K, Fong S K, Stroud R M, Betlach M C
Department of Biochemistry and Biophysics, University of California, San Francisco 94143-0448.
Biochemistry. 1991 Mar 26;30(12):3082-8. doi: 10.1021/bi00226a015.
The integral membrane protein bacterioopsin, found in the extremely halophilic archaebacterium Halobacterium halobium, was expressed in Escherichia coli as a fusion protein containing 13 heterologous amino acids at the amino terminus. The expressed protein was localized primarily to the E. coli cytoplasmic membrane (greater than 80%) and had an in vivo half-life of 26 min. The amount of bacterioopsin in E. coli crude lysates was quantitated immunologically from Western blots and was expressed at 10-20-fold higher levels than seen previously (i.e., 17 mg/L; 5.6% of the total protein). Three distinct forms of the protein were detected immunologically: two of the forms were generated by the removal of either one or four amino acid residues at the amino terminus; the third form remained unaltered.
视紫红质是一种整合膜蛋白，存在于极端嗜盐古细菌盐生盐杆菌中。它在大肠杆菌中作为一种融合蛋白表达，该融合蛋白在氨基末端含有13个异源氨基酸。表达的蛋白主要定位于大肠杆菌细胞质膜（大于80%），其体内半衰期为26分钟。通过蛋白质印迹法对大肠杆菌粗裂解物中的视紫红质含量进行免疫定量，其表达水平比之前观察到的高10至20倍（即17 mg/L；占总蛋白的5.6%）。通过免疫检测到该蛋白有三种不同形式：其中两种形式是通过去除氨基末端的一个或四个氨基酸残基产生的；第三种形式保持不变。
