著者

Shingo MARUMO Hiroyuki HATTORI Hiroshi ABE Yoshio NONOYAMA Katsura MUNAKATA

出版者

Japan Society for Bioscience, Biotechnology, and Agrochemistry

雑誌

Agricultural and Biological Chemistry (ISSN:00021369)

巻号頁・発行日

vol.32, no.4, pp.528-529, 1968 (Released:2008-11-27)

参考文献数

7

被引用文献数

3 13

著者

PARK Jae-Seon HORINOUCHI Sueharu BEPPU Teruhiko

出版者

社団法人日本農芸化学会

雑誌

Agricultural and Biological Chemistry (ISSN:00021369)

巻号頁・発行日

vol.55, no.7, pp.1745-1750, 1991-07-23

被引用文献数

8

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An endo-type semi-alkaline cellulase (CMCase I) produced by an alkalophilic Streptomyces strain has an extraordinarily long leader peptide of about 70 amino acids (aa), which can be grouped into four distinct regions, an NH2-terminal region (13aa), an Arg-cluster region (13aa), a hydrophobic region (23aa), and an Ala/Pro-repeat region (12aa). For identification of the function of each part of the leader peptide for secretion of the enzyme, mutations in the leader peptide were generated by site-directed mutagenesis using the cloned gene, and the mutant genes were expressed in a cellulase-negative mutant strain, Streptomyces lividans HN1. Although all the alterations in the leader peptide, except for one case, decreased secretion to various extents, in S. lividans, the following conclusions were obtained. Comparison of the intra- and extra-cellular enzyme activities of the mutants suggested that the Arg-cluster region was essential in secretion of the cellulase. Deletion of 8 amino acids rich in threonine and proline in the NH_2-terminal region enhanced the secretion to a small extent. Deletion of the Ala/Pro repeat region had almost no effect on secretion.

著者

AL-MASHIKHI S.A. NAKAI Shuryo

出版者

社団法人日本農芸化学会

雑誌

Agricultural and Biological Chemistry (ISSN:00021369)

巻号頁・発行日

vol.51, no.11, pp.2881-2887, 1987-11-23

被引用文献数

19

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Immobilized metal affinity chromatography (IMAC) was used to separate ovotransferrin (OVT) by a single chromatographic step. Ovotransferrin was bound strongly to immobilized copper ions, while other components of egg white passed through the column. Using acidic pH and/or a strong competing solute, imidazole, ovotransferrin was recovered in 94〜98% pure form as indicated by SDS-polyacrylamide gel electrophoresis and immunoelectrophoresis. The elution profiles from the IMAC column indicated the presence of two forms of ovotransferrin. The capacity of the IMAC column was 20mg OVT/ml copper loaded gel. Saturation of the metal binding sites of ovotransferrin with Fe^<2+> and Cu^<2+> did not interfere with the binding of ovotransferrin to the IMAC column. However, modification of the histidine residues in ovotransferrin with diethyl pyrocarbonate almost completely destroyed the binding to the IMAC column.