| Project/Area Number |
16208010
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (A)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
Applied microbiology
|
|---|
| Research Institution | Hiroshima University |
|---|
Principal Investigator |
KINASHI Haruyasu Hiroshima University, Graduate School of Advanced Sciences of Matter, Professor, 大学院先端物質科学研究科, 教授 (80224997)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
ARAKAWA Kenji Hiroshima University, Graduate School of Advanced Sciences of Matter, Assistant, 大学院先端物質科学研究科, 助手 (80346527)
|
|---|
| Project Period (FY) |
2004 – 2006
|
| Project Status |
Completed (Fiscal Year 2006)
|
| Budget Amount *help |
¥50,050,000 (Direct Cost: ¥38,500,000、Indirect Cost: ¥11,550,000)
Fiscal Year 2006: ¥10,400,000 (Direct Cost: ¥8,000,000、Indirect Cost: ¥2,400,000)
Fiscal Year 2005: ¥11,830,000 (Direct Cost: ¥9,100,000、Indirect Cost: ¥2,730,000)
Fiscal Year 2004: ¥27,820,000 (Direct Cost: ¥21,400,000、Indirect Cost: ¥6,420,000)
|
|---|
| Keywords | Streptomyces / linear plasmid / transposon / chromosome inversion / y-butyrolactone / P450 / regulatory cascade / polyketide biosynthesis / ランカサイジン / incompatibility / ランカマイシン / 線状染色体 / ゲノム再編成 / 抗生物質 / ポリケチド / 生合成 |
|---|
| Research Abstract |
(1) We revealed that the chromosomal inversion found in Streptomycesgriseus 402-2 occurred by transposition of a transposonfollowedbyhomologousrecombinationbetweenthe old and new transposons.Consequently, we identified chimeric direct repeat sequences at both ends of the two transposons in strain 402-2.
(2) We revealed that a series of linear plasmids in S. violaceoruber JCM4979 were formed by amplification of a 36-kb DNA unit comprising of SCP1 and SCP2 fragments in SCP1. It is quite interesting that these linear plasmids are compatible in spite of their identical oriC sequence.
(3) The structure of LC-KA05 produced by an amine oxidasemutantof S. rochefindicated that oxidation of an amide intermediate to an imide followed by nucleophilic attack by C2 formed the unique 17-membered ring of lankacidin. Heterologous expression of the Ikc cluster in S. lividans and the lkcFG gene fusion experiment supported our modular-iterative polyketide biosynthesis hypothesis for lankacidin.
(4) Feeding and gene targeting experiments revealed that isoleucine was oxidized to 2-methylbutyrate and incorporated into the 8,15-didexylankanolide skeleton, and then hydroxylated at the 15 and 8 positions by LkmK and LkmF, respectively.
(5) We revealed that srrX-srrA make a y-butyrolactone-receptor system in S. rochei. The srrX gene showed a positive effect on antibiotic production and a negative effect on spore formation, while, srrA reversed both effects of srrX. Extensive transcriptional analysis confirmed the signaling pathway from srrX through srrA to srrY. We also identified two SrrA binding sites upstream of the srrY gene, which contained a palindromic sequence for GB-receptors and repeat sequences for SARP proteins, respectively.
|
