Collagen is a major component of connective tissue and accounts for a third of total body protein. Collagen catabolism occurs under both normal and pathological conditions; thus, an understanding of the mechanism of degradation of collagen is essential to all processes that involve connective tissue remodeling and repair. Collagenases are enzymes that are capable of hydrolyzing collagen. Bacterial and tissue collagenases differ in their mode of hydrolysis of the collagen molecule. The work in this thesis describes the kinetics of hydrolysis of the interstitial collagens by both bacterial and human collagenases. / In order to facilitate kinetic studies, an accurate, sensitive and quantitative assay for collagenases has been developed that is based on the hydrolysis of radiolabeled collagens. This assay has been used to generate double-reciprocal plots for the hydrolysis of types I, II and III collagens by the bacterial collagenases derived from Clostridium histolyticum and the tissue collagenases isolated and purified from human neutrophils and human fibroblasts. These studies indicate that human neutrophil collagenase (HNC) preferentially hydrolyzes type I collagen over types II and III collagens. In contrast, human fibroblast collagenase (HFC) prefers type III collagen over types I and II. The Clostridial collagenases do not discriminate between the various types of collagens. A comparison of the k$\sb{\rm cat}$/K$\sb{\rm M}$ values toward hydrolysis of rat type I collagen shows that HNC is more potent than either HFC or the Clostridial collagenases. / The inhibition of HNC by six gold(I) compounds used in the treatment of rheumatoid arthritis has also been investigated. The mechanism by which gold(I) compounds provide remission in rheumatoid arthritis, however, is not understood. Since type II collagen is a major component of joint cartilage and since HNC can hydrolyze type II collagen, the possibility that gold(I) compounds are inhibitions of HNC was investigated. All six gold(I) compounds studied inhibited the p-chloromercuribenzoate-activated latent HNC with varying potencies. Kinetic studies shows that the inhibition is non-competitive and is reversed by zinc. Based on these studies, a model showing the metal binding sites in latent HNC is proposed. / Source: Dissertation Abstracts International, Volume: 49-08, Section: B, page: 3166. / Major Professor: Harold E. Van Wart. / Thesis (Ph.D.)--The Florida State University, 1988.
| Identifer | oai:union.ndltd.org:fsu.edu/oai:fsu.digital.flvc.org:fsu_77840 |
| Contributors | Mallya, Satish Keshav., Florida State University |
| Source Sets | Florida State University |
| Language | English |
| Detected Language | English |
| Type | Text |
| Format | 239 p. |
| Rights | On campus use only. |
| Relation | Dissertation Abstracts International |
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