Evidence that latent collagenases are enzyme-inhibitor complexes

Sellers, Anthony; Cartwright, Edward; Murphy, Gillian; Reynolds, J J

doi:10.1042/bj1630303

Cited by 212 publications

(86 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…It is conceivable that non-covalently associated protein(s) or peptide(s) may be responsible for maintaining the inactive state of the precursor, and that their degradation by proteases could result in the precursor now exposing its active site. Such a situation has been observed with latent collagenase (mammalian) which is inactive due to the presence of a non-covalently attached inhibitor peptide [20]. In fact, as noted earlier, the results shown in Fig.…”

Section: Discussionsupporting

confidence: 69%

Mechanisms of activation and secretion of a cell‐associated precursor of an exocellular protease of Pseudomonas aeruginosa 34362A

Fecycz

Campbell

1985

European Journal of Biochemistry

View full text Add to dashboard Cite

An inactive precursor to the active exocellular protease 1 of Pseudomonas aeruginosa is cell-associated and located primarily in the periplasmic space. We have studied factors that bring about activation of the precursor in vitro in order to shed some light on the process of its activation and secretion in vivo. A variety of diverse procedures were shown to effect irreversible activation. Several mild non-enzymatic procedures were effective, such as dialysis of an ammonium sulfate precipitate against neutral buffers, gel filtration (Sephadex G-loo), and ion-exchange chromatography (DEAE-cellulose). Activation also resulted following treatment with anionic detergents (sodium dodecyl sulfate, N-lauroyl sarcosine) and deoxycholate. Limited exposure to any of-several proteases with different specificities also resulted in activation. The kinetics of detergent-catalyzed activation reveals a long lag followed by rapid activation, suggesting at least a two-stage process. The precursor and the mature protease 1 have indistinguishable molecular masses (33 kDa), as measured by sodium dodecyl sulfate/ polyacrylamide gel electrophoresis of these proteins purified by immunoabsorbance chromatography under denaturing conditions. Further, both precursor and protease have identical N-terminal alanine. Our results suggest that it is improbable that activation is the result of proteolytic processing of the precursor itself, but rather that it may involve the removal of a non-covalently associated inhibitor molecule. Hydrophobic interaction chromatography on octyl-Sepharose revealed that activation was accompanied by a significant change in the hydrophobicity, pointing to a significant change in the conformation of the precursor and the mature protease.A mutant has been studied which accumulates activatable precursor in the periplasm but releases no active enzyme into the culture medium, supporting the hypothesis that secretion through the inner and outer membranes proceed by different mechanisms. Comparison of outer membranes of protease-secreting strains (34 362A and PAKS 1) and a protease-negative mutant (PAKS 18) which accumulates precursor has shown that there is a change in the outer membrane protein profile in the latter.

show abstract

Section: Discussionsupporting

confidence: 69%

Mechanisms of activation and secretion of a cell‐associated precursor of an exocellular protease of Pseudomonas aeruginosa 34362A

Fecycz

Campbell

1985

European Journal of Biochemistry

View full text Add to dashboard Cite

show abstract

“…Pro-MMPs could be artificially activated by organomercuric reagents such as p-APMA in vitro (8). In the present study, several gelatinolytic active bands were newly induced or enhanced by the p-APMA treatment in the extracts of the skin, jejunum, and muscle (Fig.…”

Section: Discussionmentioning

confidence: 79%

“…It has been demonstrated that pro-MMP is activated by p-APMA (8). Then, in order to detect latent gelatinolytic activities due to MMPs in the normal organs, each extract was incubated with,p-APMA before zymographic analysis.…”

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

Novel gelatinolytic activities in rat organs

et al. 1999

View full text Add to dashboard Cite

Summary: Novel gelatinolytic activities in both latent and active forms were detected in the normal organs of rat by gelatin zymography. Multiple active bands were detected in the extracts from the skin, jejunum, muscle, and kidney without any activation. These activities were inhibited by 1,10-phenanthroline or leupeptin, nor by E64, suggesting that these activities were derived from metallo-proteinases or serine-proteinases. Some gelatinolytic active bands were newly induced or enhanced by p-aminophenylmercuric acetate. These results suggest that matrix degrading activities due to metallo-and serine-proteinases were constitutively expressed in various rat normal organs.

show abstract

“…The question of the nature of the observed latency of the secreted forms of metalloproteinases occupied many of the laboratories over the next few years (14). In 1978, Stricklin et al (15) had shown that purified latent collagenase could be activated by trypsin treatment, and we and others had found that treatment with organomercurials could also activate the rabbit bone enzyme (16). It was proposed that these might act to dissociate a complex of collagenase and the natural inhibitor, but this was later dismissed as it became evident that the matrixdegrading metalloenzymes were secreted in an N-terminally extended pro form and that propeptide cleavage was needed to generate the full activity.…”

Section: A Brief Early Historymentioning

confidence: 99%

Riding the metalloproteinase roller coaster

Murphy

2017

Journal of Biological Chemistry

View full text Add to dashboard Cite

To many of us in the field, working on matrix metalloproteinases (MMPs) has felt like riding a roller coaster, traveling through times of both excitement and despair. I was fortunate to join the ride when it was a mere carousel of three activities thought to target the proteins that comprise the extracellular matrix (ECM). New technologies brought the thrills of discovery as we uncovered specific proteinase genes and defined specialized activities in different cellular processes. The MMPs and the sister families of "a disintegrin and metalloproteinase" (ADAMs), ADAMs with thrombospondin domains (ADAM-TS), and Astacins are now recognized as key signaling "scissors" that drive rapid changes in a plethora of cellular pathways. My many excellent colleagues and collaborators and I were enthused to contribute to the early development of the field and continue to be amazed at its growth and sophistication. In contrast, the hype and failure of early inhibitor discovery have dogged our standing with the pharmaceutical industry and grant-giving bodies. However, the true believers have kept going, and knowledge of particular functions of MMPs and their contributions to disease progression has progressed. Recognition of the strategic importance of proteinase function should inspire more work harnessing new technologies such as imaging, proteomics, and gene editing to generate a more precise understanding of individual situations. New approaches to inhibitor design and assessment are possible, and the consequent ability to precisely abrogate specific MMP activity could contribute to the fight against a number of pathologies with unmet needs. What a ride it could be!

show abstract

Evidence that latent collagenases are enzyme-inhibitor complexes

Cited by 212 publications

References 21 publications

Mechanisms of activation and secretion of a cell‐associated precursor of an exocellular protease of Pseudomonas aeruginosa 34362A

Mechanisms of activation and secretion of a cell‐associated precursor of an exocellular protease of Pseudomonas aeruginosa 34362A

Novel gelatinolytic activities in rat organs

Riding the metalloproteinase roller coaster

Contact Info

Product

Resources

About