| Project/Area Number |
11670268
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Bacteriology (including Mycology)
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| Research Institution | Osaka Prefecture University |
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Principal Investigator |
KOZAKI Shunji Osaka Precture University, Graduate School of Agriculture and Biological Sciences. Professor., 農学生命科学研究科, 教授 (10109895)
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| Project Period (FY) |
1999 – 2000
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| Project Status |
Completed (Fiscal Year 2000)
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| Budget Amount *help |
¥3,500,000 (Direct Cost: ¥3,500,000)
Fiscal Year 2000: ¥1,300,000 (Direct Cost: ¥1,300,000)
Fiscal Year 1999: ¥2,200,000 (Direct Cost: ¥2,200,000)
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| Keywords | Clostridium botulinum / neurotoxin / receptor / mutant |
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| Research Abstract |
We examined properties of the neurotoxin (111/NT) produced by the organism which had been associated with the first type B infant botulism and compared with the nerutoxin (Okra/NT) of the authentic strain. The data indicate that the toxicity of 111/NT was lower than that of Okra/NT, being due to the receptor binding capability. In fact the neucleotide sequence analysis suggest that the receptor binding domains between the two toxins share different amino acid residues and about 70% of these residues expect to be exposed to the surface on the toxin molecule. We are now in progress to examine the the receptor binding abilities of various mutants of the toxin binding domain in order to clarify the recognition site.
Synaptotagmin II is the protein receptor for the neurotoxin and has the toxin binding site on the amine-terminal region involving 60 amino acid residues. Overall, 40 site-directed and deleted mutants were prepared to examine their toxin binding activity. The data showed that six amino acid residues are related with the toxin binding. Such critical amino acid residues are located in the 41 to 60 residues from the amino termius, indicating that the 20 residues function as the toxin recognition site.
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