Analysis of regulatory mechanism of expression of drug-resistance genes and their evolution
Grant-in-Aid for Scientific Research (B).
|Research Institution||MEIJI COLLEGE OF PHARMACY|
OGAWARA Hiroshi Meiji College of Pharmacy, 薬学部, 教授 (00097198)
URABE Hiroaki Assistant Professor, 薬学部, 助手 (20201361)
HIGASHI Kyoichiro Assistant Professor, 薬学部, 助手 (10189748)
|Project Fiscal Year
1992 – 1994
Completed(Fiscal Year 1994)
|Budget Amount *help
¥2,000,000 (Direct Cost : ¥2,000,000)
Fiscal Year 1994 : ¥1,000,000 (Direct Cost : ¥1,000,000)
Fiscal Year 1993 : ¥1,000,000 (Direct Cost : ¥1,000,000)
|Keywords||drug resistance / gene expression / beta-lactamase / penicillin-binding protein / nucleotide sequence / evolution / pseudogene / 薬剤耐性 / 遺伝子発現 / β-ラクタマーゼ / ペニシリン結合蛋白質 / ヌクレオチド配列 / 進化 / 偽遺伝子 / 薬剤耐性遺伝子 / 放線菌 / beta-ラクタマーゼ / アクチベータータンパク質 / β-ラクタメース / クローニング|
(1) Analysis of activator-regulator genes for beta-lactamase in Streptomyces cacaoi.
There were two activator-regulator genes in the upstream of the structural gene of the beta-lactamase. Transcription for the activator genes commenced at the translational initiation codon or within a few nucleotides from the translational start site. These genes are also necessary for the induction.
(2) Sequence analysis of three type II beta-lactamases from Streptomyces.
The deduced amino acid sequences of beta-lactamases from S.cellulosae KCCS0127, S.lavendulae KCCS0263 and S.fradiae Y59 were very close to those of class A beta-lactamases but completely different from class D beta-lactamases. This is contrary to the expectation from their substrate specificity and their property of binding blue dextran and NADP^+.
(3) Analysis of amino acid sequences involved in the binding to blue-dextran.
To determine which amino acid residues are critical in binding activity to blue dextran, chimera beta-lactamases we
re constructed and their binding abilities were determined. Blue dextran binding may depend more on overall conformation of about two-thirds of the beta-lactamase molecule from the N-terminus than on the primary structure.
(4) Analysis of sequence similarity of beta-lactamases and their phylogenetic tree.
A phylogenetic tree constructed on the basis of the amino acid sequences of 47 beta-lactamases and the computeraided analysis suggests that beta-lactamases can be classified into six groups. The tree provides more detailed classification and time-scale mutual relationships and predicts new types of p-lactamases that may be found. In addition, the class A beta-lactamases are clearly divided into three groups and some eukaryotic proteins have a low but significant evolutionary relatedness.
(5) Gene transfer of a part of beta-lactamase gene?
The amino acid sequence deduced from the nucleotide sequence of the upstream region of cytochrome c oxidase subunit II from Paracoccus denitrificans had an unusually high score of homology to that of a portion of beta-lactamases from Gram-negative bacteria. It is suggested that the nucleotide sequence was positioned by a transfer of a part of a beta-lactamase gene formed as a result of gene duplication or it was formed by a deletion of the essential region of the beta-lactamase gene.
(6) Similarity analysis of beta-lactam-interacting proteins and the phylogenetic tree.
Fifty tree beta-lactam-interacting proteins were classidied to six groups. Three DD-peptidases from Streptomycetes were distinguished into three different groups. Together with the fact that apparently unrelated proteins like Pseudomonas esterase and O.anthropi D-aminopeptidase show high scores of similarity, it is speculated that these beta-lactam-interacting proteins including beta-lactamases now are formed as a result of very rapid divergent evolution, and the esterase and D-aminopeptidase activities in these proteins may be acquired as a result of such rapid evolution. Less
Research Output (30results)