Murasugi A, Wada C, Hayashi Y
J Biochem. 1983 Feb;93(2):661-4. doi: 10.1093/oxfordjournals.jbchem.a134222.
Two kinds of Cd-binding peptides (Cd-BP1 and Cd-BP2) are induced in fission yeast upon addition of CdCl2 to the culture medium (l). It was also reported that Cd-BP1 and Cd-BP2 consisted of the same components, unit peptides (Cys3, Glu3, Gly1) and Cd atoms, though the respective amounts of components in each molecule were different (1, 2). Now, we have found that Cd-BP1 contains about 1 mol of acid-labile sulfide per mol, and Cd-BP2 contains no labile sulfide. The existence of the labile sulfide explains the unique physicochemical characteristics of Cd-BP1. Since acid-labile sulfide has not been found in metallothioneins or other metallothionein-like metal-binding proteins, the occurrence of labile sulfide in Cd-BP1 is the first instance in this field.
向裂殖酵母的培养基中添加氯化镉（CdCl₂）后，可诱导产生两种镉结合肽（Cd - BP1和Cd - BP2）(1)。也有报道称，Cd - BP1和Cd - BP2由相同的成分组成，即单位肽（Cys3、Glu3、Gly1）和镉原子，尽管每个分子中各成分的含量不同(1, 2)。现在，我们发现Cd - BP1每摩尔含有约1摩尔酸不稳定硫化物，而Cd - BP2不含不稳定硫化物。不稳定硫化物的存在解释了Cd - BP1独特的物理化学特性。由于在金属硫蛋白或其他类金属硫蛋白金属结合蛋白中未发现酸不稳定硫化物，Cd - BP1中不稳定硫化物的出现是该领域的首例。
