JB
Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
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
Services
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 arrowReprints and Permissions
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Reilly, T. J.
Right arrow Articles by Smith, A. L.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Reilly, T. J.
Right arrow Articles by Smith, A. L.

Journal of Bacteriology, November 1999, p. 6797-6805, Vol. 181, No. 21
0021-9193/99/$04.00+0
Copyright © 1999, American Society for Microbiology. All rights reserved.

Outer Membrane Lipoprotein e (P4) of Haemophilus influenzae Is a Novel Phosphomonoesterase

Thomas J. Reilly, Deborah L. Chance, and Arnold L. Smith*

Department of Molecular Microbiology and Immunology, University of Missouri Medical School, Columbia, Missouri 65212

Received 24 May 1999/Accepted 10 August 1999

Haemophilus influenzae exists as a commensal of the upper respiratory tract of humans but also causes infections of contiguous structures. We describe the identification, localization, purification, and characterization of a novel, surface-localized phosphomonoesterase from a nontypeable H. influenzae strain, R2866. Sequences obtained from two CNBr-derived fragments of this protein matched lipoprotein e (P4) within the H. influenzae sequence database. Escherichia coli DH5alpha transformed with plasmids containing the H. influenzae hel gene, which encodes lipoprotein e (P4), produced high levels of a membrane-associated phosphomonoesterase. The isolated ~28-kDa enzyme was tartrate resistant and displayed narrow substrate specificity with the highest activity for arylphosphates, excluding 5-bromo-4-chloro-3-indolylphosphate. Optimum enzymatic activity was observed at pH 5.0 and only in the presence of divalent copper. The enzyme was inhibited by vanadate, molybdate, and EDTA but was resistant to inorganic phosphate. The association of phosphomonoesterase activity with a protein that has also been recognized as a heme transporter suggests a unique role for this unusual phosphohydrolase.

* Corresponding author. Mailing address: Department of Molecular Microbiology and Immunology, DCO 44.00 M616 Medical Sciences Bldg., UMC School of Medicine, Columbia, MO 65212. Phone: (573) 882-8152. Fax: (573) 882-4287. E-mail: smithal{at}health.missouri.edu.

Journal of Bacteriology, November 1999, p. 6797-6805, Vol. 181, No. 21
0021-9193/99/$04.00+0
Copyright © 1999, American Society for Microbiology. All rights reserved.


This article has been cited by other articles:



Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
Appl. Environ. Microbiol. Infect. Immun. Eukaryot. Cell
Mol. Cell. Biol. J. Virol. Microbiol. Mol. Biol. Rev.
ALL ASM JOURNALS

Copyright © 1999 by the American Society for Microbiology. All rights reserved.