Canard B, Garnier T, Saint-Joanis B, Cole S T
Unité de Génétique Moléculaire Bactérienne, Institut Pasteur, Paris, France.
Mol Gen Genet. 1994 Apr;243(2):215-24. doi: 10.1007/BF00280319.
A recombinant lambda phage was identified in a Clostridium perfringens genomic library by means of its ability to hydrolyse the fluorescent substrate 4-methyl-umbelliferyl-beta-D-glucosaminide, isolated and shown to encode an endo-beta-N-acetylglucosaminidase. This enzyme, NagH, is also known as hyaluronidase, or Mu toxin, a putative virulence factor which is likely to act on connective tissue during gas gangrene. Nucleotide sequence analysis allowed the primary structure to be deduced and showed hyaluronidase to be a large exported protein of 114,392 Daltons and an enzyme of this size, endowed with the corresponding activities, was partially purified from C. perfringens. Hyaluronidase seems to be organised into two domains, an N-terminal region comprising 700 amino acids bearing the active site and a 300-residue C-terminal segment, containing three copies of an extended motif. Two other reading frames, linked to nagH, also appear to encode proteins with sugar-binding motifs.
通过其水解荧光底物4-甲基伞形酮-β-D-氨基葡萄糖苷的能力，在产气荚膜梭菌基因组文库中鉴定出一种重组λ噬菌体，对其进行分离并显示其编码一种内切β-N-乙酰氨基葡萄糖苷酶。这种酶，即NagH，也被称为透明质酸酶或Mu毒素，是一种假定的毒力因子，在气性坏疽期间可能作用于结缔组织。核苷酸序列分析使得能够推导其一级结构，结果显示透明质酸酶是一种分子量为114,392道尔顿的大型分泌蛋白，并且从产气荚膜梭菌中部分纯化出了具有相应活性的这种大小的酶。透明质酸酶似乎由两个结构域组成，一个包含700个氨基酸且带有活性位点的N端区域和一个含有三个延伸基序拷贝的300个残基的C端片段。与nagH相连的另外两个阅读框似乎也编码具有糖结合基序的蛋白质。
