Amino Acid Sequence of Protein α-Amylase Inhibitor from Streptomyces griseosporeus YM-25

Abstract

The amino acid sequence of a protein alpha-amylase inhibitor from Streptomyces griseosporeus YM-25 (Haim II), which consists of 77 amino acid residues, including two disulfide bridges, was determined by conventional methods. One of the disulfide bridges was found to be located between Cys(6) and Cys(22), and the other between Cys(40) and Cys(67) from the results of structure analyses of the two cystine-containing peptides obtained from the thermolysin digest of the native inhibitor.

Nucleotide sequence and expression of a Streptomyces griseosporeus proteinaceous alpha-amylase inhibitor (HaimII) gene

“…This sequence probably constitutes the ribosome-binding site of the Haimll gene and resembles the ribosome-binding sites of E. coli (27,29 The amino acid sequence of HaimlI deduced from the nucleotide sequence data was 43 residues longer than the 77 amino acids of the mature HaimlI protein (20). A total of 37 amino acids preceded the amino terminus of the native HaimlI protein, while the remaining 6 residues followed the carboxyl terminus, as shown in Fig.…”

“…The pre-HaimIl protein is believed to be processed both during and after secretion. Two forms of the inhibitor, which have a higher molecular weight than that of the HaimIl protein isolated from S. griseosporeus, were partially purified from the culture filtrate of Streptomyces lividans containing the cloned HaimIl gene.Various proteinaceous alpha-amylase inhibitors from microorganisms have been isolated and characterized (3,7,9,20,33,34). These inhibitors are active against alpha-amylases of animal origin but inactive towards those of plants and microorganisms.…”

“…Various proteinaceous alpha-amylase inhibitors from microorganisms have been isolated and characterized (3,7,9,20,33,34). These inhibitors are active against alpha-amylases of animal origin but inactive towards those of plants and microorganisms.…”

“…Two isoinhibitors produced by S. griseosporeus, Haiml and Haimll, have similar inhibitory specificities and amino acid compositions but differ in their isoelectric points. The amino acid sequence of the Haimll protein has been determined by conventional sequencing methods (20) and found to bear considerable sequence homology with other alpha-amylase inhibitors from Streptomyces species, such as Hoe467A and A13688 (3, 9, 34). Furthermore, these proteins possess four cysteine residues at exactly identical positions and constitute two disulfide bonds, which make up the rigid and stable structure of the inhibitor molecules.…”

Heterologous expression of the alpha-amylase inhibitor gene cloned from an amplified genomic sequence of Streptomyces tendae

“…Proteins inhibiting human salivary gland amylases were isolated from plants (7,22) and various microorganisms (1,9,23). The ac-amylase inhibitor of Streptomyces tendae is a biochemically well-characterized acidic protein of 74 amino acids (30) secreted in large amounts into the culture medium (15).…”