Activity of matrix metalloproteinase-9 against native collagen types I and III.
Interstitial collagen types I, II and III are highly resistant to proteolytic attack, due to their triple helical structure, but can be cleaved by matrix metalloproteinase (MMP) collagenases at a specific site, approximately three-quarters of the length from the N-terminus of each chain. MMP-2 and -9 are closely related at the structural level, but MMP-2, and not MMP-9, has been previously described as a collagenase. This report investigates the ability of purified recombinant human MMP-9 produced in insect cells to degrade native collagen types I and III. Purified MMP-9 was able to cleave the soluble, monomeric forms of native collagen types I and III at 37 degrees C and 25 degrees C, respectively. Activity against collagens I and III was abolished by metalloproteinase inhibitors and was not present in the concentrated crude medium of mock-transfected cells, demonstrating that it was MMP-9-derived. Mutated, collagenase-resistant type I collagen was not digested by MMP-9, indicating that the three-quarters/one-quarter locus was the site of initial attack. Digestion of type III collagen generated a three-quarter fragment, as shown by comparison with MMP-1-mediated cleavage. These data demonstrate that MMP-9, like MMP-2, is able to cleave collagens I and III in their native form and in a manner that is characteristic of the unique collagenolytic activity of MMP collagenases.
Bigg
Heather F
HF
Musculoskeletal Research Group, Institute of Cellular Medicine, The Medical School, Framlington Place, Newcastle University, Newcastle-upon-Tyne, UK.
Rowan
Andrew D
AD
Barker
Michael D
MD
Cawston
Tim E
TE
D000818:Animals; D024042:Collagen Type I / Q000737:chemistry / Q000378:metabolism*; D024061:Collagen Type III / Q000737:chemistry / Q000378:metabolism*; D017077:Culture Media, Conditioned / Q000737:chemistry; D018076:DNA, Complementary; D004926:Escherichia coli / Q000235:genetics; D006801:Humans; D020780:Matrix Metalloproteinase 9 / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D008970:Molecular Weight; D011994:Recombinant Proteins / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism; D012995:Solubility; D018411:Spodoptera / Q000166:cytology / Q000378:metabolism; D013696:Temperature
D024042:Collagen Type I; D024061:Collagen Type III; D017077:Culture Media, Conditioned; D018076:DNA, Complementary; D011994:Recombinant Proteins; D020780:Matrix Metalloproteinase 9