J Med Microbiol NEW Faster Access
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via CrossRef
Google Scholar
Right arrow Articles by Johnson, B. T.
Right arrow Articles by Mayo, J. A.
PubMed
Right arrow PubMed Citation
Right arrow Articles by Johnson, B. T.
Right arrow Articles by Mayo, J. A.
Agricola
Right arrow Articles by Johnson, B. T.
Right arrow Articles by Mayo, J. A.
J Med Microbiol 57 (2008), 643-651; DOI: 10.1099/jmm.0.47754-0
© 2008 Society for General Microbiology
ISSN 1473-5644

Extracellular proteolytic activities expressed by Bacillus pumilus isolated from endodontic and periodontal lesions

Blair T. Johnson1,2,{dagger}, Lindsey N. Shaw3,4, Daniel C. Nelson5 and John A. Mayo1,3,6

1 Department of Microbiology, Immunology and Parasitology, School of Dentistry, Louisiana State University Health Sciences Center, New Orleans, LA 70119, USA

2 Department of Endodontics, School of Dentistry, Louisiana State University Health Sciences Center, New Orleans, LA 70119, USA

3 Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA 30602, USA

4 Department of Biology, University of South Florida, Tampa, FL 33620, USA

5 University of Maryland Biotechnology Institute, Center for Advanced Research in Biotechnology, Rockville, MD 20850, USA

6 Department of Periodontics, School of Dentistry, Louisiana State University Health Sciences Center, New Orleans, LA 70119, USA

Correspondence
John A. Mayo
jmayo{at}uga.edu

Received 6 November 2007
Accepted 5 February 2008

The purpose of the present study was to identify 12 Bacillus isolates that had been obtained from root canals of teeth requiring endodontic therapy and from periodontal pockets in severe marginal periodontitis, and to determine whether these isolates exhibited extracellular proteolytic activity and, using in vitro assays, whether any such activity could degrade substrates that would be pathophysiologically relevant with regard to the production of endodontic and periodontal lesions. Biochemical and carbohydrate fermentation patterns were used in the identification of all strains, which was confirmed by determination of the16S rRNA gene sequence for strain BJ0055. Screening for production of extracellular proteolytic activity by all strains was done with a general proteinase substrate. All isolates were identified as representing Bacillus pumilus and all exhibited extracellular proteolytic activity. The putative pathophysiological relevance of extracellular proteinase production in strain BJ0055 was assessed using fluorophore-labelled elastin and collagen and several chromogenic peptides. Probable classes of proteinases acting on each substrate were investigated using class-specific inhibitors. Activity–pH profiles were determined in buffers at different pH values. Extracellular activities that were caseinolytic, elastinolytic, collagenolytic, glutamyl endopeptidase-like, and alanyl tripeptidyl peptidase-like were observed. No trypsin-like activities were detected. Serine- and chymotrypsin-like serine proteinase activities were detected, with activity observed at neutral and alkaline, but not acidic, pH. B. pumilus strains isolated from endodontic and periodontal lesions exhibited extracellular activities that degrade elastin, collagen and other substrates. These activities may be virulence factors that contribute to tissue damage in apical periodontitis and severe marginal periodontitis.

Abbreviations: AAPV, alanyl-alanyl-prolyl-valyl; BODIPY, 4,4-difluoro-5,7-dimethyl-4-bora-3a,4a-diaza-s-indacene-3-propionic acid; DFP, di-isopropylfluorophosphate; E-64, L-trans-epoxysuccinyl-leucylamide-(4-guanidino)-butane; FL, phenylalanyl-leucyl; FLE, phenylalanyl-leucyl-glutamyl; FPA, phenylalanyl-prolyl-alanyl; GGL, glycyl-glycyl-leucyl; HPA, Hide Powder Azure; K, lysyl; L, leucyl; LTR, leucyl-threonyl-arginyl; MMP-1, matrix metalloproteinase 1 (tissue collagenase); OP, o-phenanthrolene; pNA, p-nitroanilide; R, arginyl; TLCK, tosyl lysyl chloromethyl ketone; TPCK, tosyl phenylalanyl chloromethyl ketone; TPPI, tripeptidyl-peptidase I; VLK, valyl-leucyl-lysyl.

{dagger}Present address: Oral & Maxillofacial Surgery Associates of Eau Claire, 1120 Oak Ridge Drive, Eau Claire, WI 54701, USA.






HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
INT J SYST EVOL MICROBIOL J MED MICROBIOL MICROBIOLOGY J GEN VIROL ALL SGM JOURNALS
Copyright © 2008 Society for General Microbiology.