当前位置： SCI文献检索 > JOURNAL OF MICROBIOLOGY AND BIOTECHNOLOGY期刊下所有文献 > Characterization of mutations in AlHK1 gene from Alternaria longipes: implication of limited function of two-component histidine kinase on conferring dicarboximide resistance.

Characterization of mutations in AlHK1 gene from Alternaria longipes: implication of limited function of two-component histidine kinase on conferring dicarboximide resistance.

Abstract：

:Four series (S, M, R, and W) of Alternaria longipes isolates were obtained based on consecutive induction with Dimethachlon (Dim) and ultraviolet irradiation. These isolates were then characterized according to their tolerance to Dim, sensitivity to osmotic stress, and phenotypic properties. All the induced Dim-resistant isolates showed a higher osmosensitivity than the parental strains, and the last generation was more resistant than the first generation in the M, R, and W series. In addition, the changes in the Dim resistance and osmotic sensitivity were not found to be directly correlated, and no distinct morphologic characteristics were found among the resistant and sensitive isolates, with the exception of the resistant isolate K-11. Thus, to investigate the molecular basis of the fungicide resistance, a group III two-component histidine kinase (HK) gene, AlHK1, was cloned from nineteen A. longipes isolates. AlHK1p was found to be comprised of a six 92- amino-acid repeat domain (AARD), HK domain, and response regulator domain, similar to the Os-1p from Neurospora crassa. A comparison of the nucleotide sequences of the AlHK1 gene from the Dim-sensitive and -resistant isolates revealed that all the resistant isolates contained a single-point mutation in the AARD of AlHK1p, with the exception of isolate K-11, where the AlHK1p contained a deletion of 107 amino acids. Moreover, the AlHK1p mutations in the isolates of each respective series involved the same amino acid substitution at the same site, although the resistance levels differed significantly in each series. Therefore, these findings suggested that a mutation in the AARD of AlHK1p was not the sole factor responsible for A. longipes resistance to dicarboximide fungicides.

journal_name

J Microbiol Biotechnol

journal_title

Journal of microbiology and biotechnology

authors

Luo Y,Yang J,Zhu M,Yan J,Mo M,Zhqng K

subject

Has Abstract

pub_date

2008-01-01 00:00:00

pages

15-22

issue

eissn

1017-7825

issn

1738-8872

pii

7106

journal_volume

pub_type

杂志文章

在线工具

Characterization of mutations in AlHK1 gene from Alternaria longipes: implication of limited function of two-component histidine kinase on conferring dicarboximide resistance.