Collagenase unwinds triple-helical collagen prior to peptide bond hydrolysis

Abstract

Breakdown of triple-helical interstitial collagens is essential in embryonic development, organ morphogenesis and tissue remodelling and repair. Aberrant collagenolysis may result in diseases such as arthritis, cancer, atherosclerosis, aneurysm and fibrosis. In vertebrates, it is initiated by collagenases belonging to the matrix metalloproteinase (MMP) family. The three-dimensional structure of a prototypic collagenase, MMP-1, indicates that the substrate-binding site of the enzyme is too narrow to accommodate triple-helical collagen. Here we report that collagenases bind and locally unwind the triple-helical structure before hydrolyzing the peptide bonds. Mutation of the catalytically essential residue Glu200 of MMP-1 to Ala resulted in a catalytically inactive enzyme, but in its presence noncollagenolytic proteinases digested collagen into typical 3/4 and 1/4 fragments, indicating that the MMP-1(E200A) mutant unwinds the triple-helical collagen. The study also shows that MMP-1 preferentially interacts with the alpha2(I) chain of type I collagen and cleaves the three alpha chains in succession. Our results throw light on the basic mechanisms that control a wide range of biological and pathological processes associated with tissue remodelling.

Antihypertensive properties of tilapia (Oreochromis spp.) frame and skin enzymatic protein hydrolysates

“…Generally, the DH after 4 h was greater in frame hydrolysates (10–20%) than the skin hydrolysates (lower than 10%). The lower DH value for skin hydrolysates might be due to the triple-helical structure of collagen, which made SPI hard to cleave by the proteases except those belonging to the matrix metalloprotease (MMP) family like collagenases [30]. Collagen hydrolysates from other protein sources have been similarly characterized with low DH.…”

Phagocytosis and remodeling of collagen matrices

“…MMP-1, MMP-8, MMP-13, and MMP-14 (MT1-MMP) are known to target collagen type 1 [23,51,52]. MMP-2 and MMP-9 as well as the membrane bound MMP-26 target denatured collagen (gelatin) [23,51].…”

“…MMP-2 and MMP-9 as well as the membrane bound MMP-26 target denatured collagen (gelatin) [23,51]. Using fragments of MMP-1, it has been shown that MMP-1 (Δ 243-450 ) cleaves type 1 collagen when incubated with the fragment responsible for unwinding the collagen -MMP-1(Glu 200 -Ala) [52]. There is some disagreement in the literature on the specificity of TIMP-1-4 for inhibiting MMP's.…”

Metaloproteinases 1 e 7 e câncer colorretal

“…Um enigma adicional é o mecanismo pelo qual colagenases clivam a tripla hélice de colágeno, quando as dimensões do sítio ativo da colagenase e a estrutura do colágeno intersticial são consideradas 65 . O sítio de ligação do substrato da MMP-1 forma uma fenda profunda com o zinco localizado na porção inferior, e a entrada deste encaixe é de apenas 5Å de largura, o suficiente para acomodar apenas uma cadeia polipeptídica 14 .…”

“…O tecido conectivo humano tem como proteí-na estrutural principal o colágeno, sendo os tipos I, II e III os mais abundantes, proporcionando a sustentação deste tecido, além de guiarem a migração, proliferação e diferenciação celular 14 . O colágeno intersticial é composto por 3 cadeias alfa de aproximadamente 1000 resíduos com repetidas cadeias trigêmeas Gly-X-Y, onde X e Y são prolina e hidroxiprolina, respectivamente, sendo esta conformação de tripla hélice o que faz o colágeno intersticial ser resistente à maioria das proteinases.…”