Relationship between the proteolytic system and iron-acquisition of periodontal pathogens
Project/Area Number |
18592018
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Research Category |
Grant-in-Aid for Scientific Research (C)
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Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
Morphological basic dentistry
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Research Institution | Matsumoto Dental University |
Principal Investigator |
FUJIMURA Setsuo Matsumoto Dental University, School of Dentistry, Professor (40045505)
|
Project Period (FY) |
2006 – 2007
|
Project Status |
Completed (Fiscal Year 2007)
|
Budget Amount *help |
¥3,710,000 (Direct Cost: ¥3,500,000、Indirect Cost: ¥210,000)
Fiscal Year 2007: ¥910,000 (Direct Cost: ¥700,000、Indirect Cost: ¥210,000)
Fiscal Year 2006: ¥2,800,000 (Direct Cost: ¥2,800,000)
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Keywords | iron acquisition / periodontal pathogen / Prevotella nigrescens / hemoglobin / hemoproteins / hemoelobin-binding protein / purification / anaerobe / エンベロープ / シデロフォア / タンパク分解酵素 / プロテアーゼ |
Research Abstract |
Since Prevotella nigrescens a periodontopathogenic gram-negative anaerobic rod lacks siderophores, this species is thought to possess particular iron-acquisition system. Actually, no growth was observed when P. nigrescens was cultured iron-depleted medium, but the growth recovered by the addition of hemin or hemoglobin. We found that this species bound to the hemoproteins such as hemoglobin and myoglobin. These findings indicate that hemoglobin binding protein (HbBP) is contained in the surface of P nigrescens. The binding was observed also in the envelope which was prepared by sonication of the cell and ultracentrifugation. The binding occurred in the pH-dependent manner; the binding was observed below neutral pHs of the incubation mixtures but not observed in the alkaline pHs. Furthermore, hemoglobin bound released from the envelope in high pH buffers. Maximum amounts hemoglobin-bound to the envelope per 1 mg was 51.2 μg. Kd for the reaction at pH 5.0 was 2.1×10^<-10>M (210 pM). From the dot blot assay, hemoglobin seemed to bind to a protein (HbBP) solubilized from the envelope by a detergent, then it was isolated by the sequential procedures including ion-exchange chromatography, affinity chromatography, and isoelectric foucusing. The purified HbBP was confirmed to bind to hemoproteins by dot blot determination. Molecular weight and isoelectric point of the HbBP was 46 kDa and 6.1, respectively.
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Report
(3 results)
Research Products
(2 results)