Bedouelle H, Bassford P J, Fowler A V, Zabin I, Beckwith J, Hofnung M
Nature. 1980 May 8;285(5760):78-81. doi: 10.1038/285078a0.
The maltose binding protein of Escherichia coli is secreted into the external periplasmic compartment of the cell by virtue of an amino-terminal signal sequence. Using DNA sequencing, we have determined the precise nature of mutations in the signal sequence which prevent the export of the maltose binding protein, causing it to accumulate in the cytoplasm in its precursor form. In most cases, the change of a single hydrophobic or uncharged amino acid to a charged amino acid within the signal sequence is sufficient to block the secretion process.
大肠杆菌的麦芽糖结合蛋白凭借氨基末端信号序列被分泌到细胞的外周质区室中。通过DNA测序，我们已经确定了信号序列中阻止麦芽糖结合蛋白输出的突变的确切性质，导致其以前体形式在细胞质中积累。在大多数情况下，信号序列内单个疏水或不带电荷的氨基酸变为带电荷的氨基酸就足以阻断分泌过程。
