Uversky V N, Leontiev V V, Gudkov A T
Institute of Protein Research, Academy of Sciences of Russia, Pushchino, Moscow Region.
Protein Eng. 1992 Dec;5(8):781-3. doi: 10.1093/protein/5.8.781.
The triple amino acid replacement (Asp10-->His, Asn101-->Asp, Arg148-->Ser) in T4 phage lysozyme was carried out by site-directed mutagenesis. At acid pH (2.7) the mutant is in a conformational state with the properties of the molten globule: (i) the mutant protein molecule is essentially compact; (ii) its CD spectrum in the near UV region is drastically reduced in intensity as compared with the wild type protein spectrum; (iii) the CD spectrum in the far UV region indicates the presence of pronounced secondary structure in the mutant; (iv) unlike the wild type protein the mutant protein can bind the hydrophobic fluorescent probe, ANS.
通过定点诱变对T4噬菌体溶菌酶进行了三重氨基酸置换（天冬氨酸10位替换为组氨酸、天冬酰胺101位替换为天冬氨酸、精氨酸148位替换为丝氨酸）。在酸性pH值（2.7）下，该突变体处于具有熔球态性质的构象状态：（i）突变蛋白分子基本紧凑；（ii）与野生型蛋白光谱相比，其近紫外区域的圆二色光谱强度大幅降低；（iii）远紫外区域的圆二色光谱表明突变体中存在明显的二级结构；（iv）与野生型蛋白不同，突变蛋白能够结合疏水荧光探针ANS。
