摘要
In order to clarify the mechanism for the inhibitory action of the Bacillus subtilis strain HAS on Sporisorium scitamineum ( Syd. ), which can cause sugarcane smut, the full-length TasA gene which encodes a protein with broad-spectrum antimicrobial activity, was PCR-amplified from HAS, and cloned into pMD18-T vector. Sequence analysis indicated that the full-length TasA cloned from HAS consisted of 786 nucleotides, and shared 99% homology in nucleotide sequence with the TasA gene sequence published in Genbank (AJ871386.1). It was predicted that the molecular weight of TasA protein was about 28 kD. Base transitions or transversions ~curred at positions 104, 164, 169,250, 399,623 and 627, at the 2nd, 2nd, 3rd , 1st , 3rd, 2nd and 3rd bases of TasA codons. The mutations in the seven bases may cause the missense mutations of the polypeptide chain. Compared with the amino acid sequences of the TasA protein encoded by Bacillus aubtilis subsp, subtilis str. 168, mutations in two amino acids at positions 150 and 209 of the protein encoded by the cloned TasA gene were found, and as a result, an ala- nine was replaced with a threonine.
In order to clarify the mechanism for the inhibitory action of the Bacillus subtilis strain HAS on Sporisorium scitamineum ( Syd. ), which can cause sugarcane smut, the full-length TasA gene which encodes a protein with broad-spectrum antimicrobial activity, was PCR-amplified from HAS, and cloned into pMD18-T vector. Sequence analysis indicated that the full-length TasA cloned from HAS consisted of 786 nucleotides, and shared 99% homology in nucleotide sequence with the TasA gene sequence published in Genbank (AJ871386.1). It was predicted that the molecular weight of TasA protein was about 28 kD. Base transitions or transversions ~curred at positions 104, 164, 169,250, 399,623 and 627, at the 2nd, 2nd, 3rd , 1st , 3rd, 2nd and 3rd bases of TasA codons. The mutations in the seven bases may cause the missense mutations of the polypeptide chain. Compared with the amino acid sequences of the TasA protein encoded by Bacillus aubtilis subsp, subtilis str. 168, mutations in two amino acids at positions 150 and 209 of the protein encoded by the cloned TasA gene were found, and as a result, an ala- nine was replaced with a threonine.
基金
Supported by National Natural Science Foundation of China(31471555)
Natural Science Foundation of Hainan Province(314120)
Earmarked Fund for Modern Agro-industry Technology Research System of China(nycytx-24)