Human sputum cathepsin B degrades proteoglycan, is inhibited by a2-macroglobulin and modulated by neutrophil elastase cleavage of cathepsin B precursor and cystatin C
(1991) In Biochemical Journal 276. p.325-331- Abstract
- The high-Mr alkali-stable form of cathepsin B was purified from purulent human sputum. It was shown to solubilize proteoglycan monomer entrapped in polyacrylamide at a rate comparable with that of human lysosomal cathepsin B. Like the enzyme from lysosomes, sputum cathepsin B was bound by human alpha 2-macroglobulin, which inhibited its action on proteoglycan. Cystatin C in purulent sputum was shown to be the N-terminally truncated form generated by neutrophil elastase cleavage, and sputum cathepsin B was only weakly inhibited by recombinant cystatin C that had been cleaved by neutrophil elastase in vitro. Addition of neutrophil elastase to mucoid sputum led to a 5-fold increase in cathepsin B activity concomitant with a lowering in Mr of... (More)
- The high-Mr alkali-stable form of cathepsin B was purified from purulent human sputum. It was shown to solubilize proteoglycan monomer entrapped in polyacrylamide at a rate comparable with that of human lysosomal cathepsin B. Like the enzyme from lysosomes, sputum cathepsin B was bound by human alpha 2-macroglobulin, which inhibited its action on proteoglycan. Cystatin C in purulent sputum was shown to be the N-terminally truncated form generated by neutrophil elastase cleavage, and sputum cathepsin B was only weakly inhibited by recombinant cystatin C that had been cleaved by neutrophil elastase in vitro. Addition of neutrophil elastase to mucoid sputum led to a 5-fold increase in cathepsin B activity concomitant with a lowering in Mr of the cysteine proteinase from 40,000 to 37,000, i.e. the size of the active enzyme purified from purulent sputum. It is concluded that the high-Mr form of cathepsin B present in purulent sputum is a functional proteinase, unlike similar forms of the enzyme secreted by mammary gland in organ culture. The activity of cathepsin B in sputum is modulated by neutrophil elastase, by a combination of inhibitor inactivation and zymogen activation. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/1106089
- author
- Buttle, David J ; Abrahamson, Magnus LU ; Burnett, David ; Mort, John S ; Barrett, Alan J ; Dando, Pamela M and Hill, Susan L
- organization
- publishing date
- 1991
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Biochemical Journal
- volume
- 276
- pages
- 325 - 331
- publisher
- Portland Press
- external identifiers
-
- scopus:0025848068
- ISSN
- 0264-6021
- language
- English
- LU publication?
- yes
- id
- c862b24b-8bd4-4d73-96df-c88fb8d1fa1f (old id 1106089)
- alternative location
- http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pubmed&pubmedid=1710889
- http://www.biochemj.org/bj/276/bj2760325.htm
- date added to LUP
- 2016-04-01 16:33:59
- date last changed
- 2021-08-29 03:13:33
@article{c862b24b-8bd4-4d73-96df-c88fb8d1fa1f, abstract = {{The high-Mr alkali-stable form of cathepsin B was purified from purulent human sputum. It was shown to solubilize proteoglycan monomer entrapped in polyacrylamide at a rate comparable with that of human lysosomal cathepsin B. Like the enzyme from lysosomes, sputum cathepsin B was bound by human alpha 2-macroglobulin, which inhibited its action on proteoglycan. Cystatin C in purulent sputum was shown to be the N-terminally truncated form generated by neutrophil elastase cleavage, and sputum cathepsin B was only weakly inhibited by recombinant cystatin C that had been cleaved by neutrophil elastase in vitro. Addition of neutrophil elastase to mucoid sputum led to a 5-fold increase in cathepsin B activity concomitant with a lowering in Mr of the cysteine proteinase from 40,000 to 37,000, i.e. the size of the active enzyme purified from purulent sputum. It is concluded that the high-Mr form of cathepsin B present in purulent sputum is a functional proteinase, unlike similar forms of the enzyme secreted by mammary gland in organ culture. The activity of cathepsin B in sputum is modulated by neutrophil elastase, by a combination of inhibitor inactivation and zymogen activation.}}, author = {{Buttle, David J and Abrahamson, Magnus and Burnett, David and Mort, John S and Barrett, Alan J and Dando, Pamela M and Hill, Susan L}}, issn = {{0264-6021}}, language = {{eng}}, pages = {{325--331}}, publisher = {{Portland Press}}, series = {{Biochemical Journal}}, title = {{Human sputum cathepsin B degrades proteoglycan, is inhibited by a2-macroglobulin and modulated by neutrophil elastase cleavage of cathepsin B precursor and cystatin C}}, url = {{http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pubmed&pubmedid=1710889}}, volume = {{276}}, year = {{1991}}, }