HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Rotanova, T. V. Articles by Wlodawer, A. Search for Related Content PubMed PubMed Citation Articles by Rotanova, T. V. Articles by Wlodawer, A. Social Bookmarking                   What's this?

REVIEW

Slicing a protease: Structural features of the ATP-dependent Lon proteases gleaned from investigations of isolated domains

¹ Shemyakin–Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow 117997, Russia
² Macromolecular Crystallography Laboratory, National Cancer Institute at Frederick, Frederick, Maryland 21702, USA
³ Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, Maryland 20892, USA
⁴ Laboratory of Cell Biology, National Cancer Institute, Bethesda, Maryland 20892, USA
⁵ Enteric Diseases Department, Infectious Diseases Directorate, Naval Medical Research Center, Silver Spring, Maryland 20910, USA

ATP-dependent Lon proteases are multi-domain enzymes found in all living organisms. All Lon proteases contain an ATPase domain belonging to the AAA⁺ superfamily of molecular machines and a proteolytic domain with a serine-lysine catalytic dyad. Lon proteases can be divided into two subfamilies, LonA and LonB, exemplified by the Escherichia coli and Archaeoglobus fulgidus paralogs, respectively. The LonA subfamily is defined by the presence of a large N-terminal domain, whereas the LonB subfamily has no such domain, but has a membrane-spanning domain that anchors the protein to the cytoplasmic side of the membrane. The two subfamilies also differ in their consensus sequences. Recent crystal structures for several individual domains and sub-fragments of Lon proteases have begun to illuminate similarities and differences in structure–function relationships between the two subfamilies. Differences in orientation of the active site residues in several isolated Lon protease domains point to possible roles for the AAA⁺ domains and/or substrates in positioning the catalytic residues within the active site. Structures of the proteolytic domains have also indicated a possible hexameric arrangement of subunits in the native state of bacterial Lon proteases. The structure of a large segment of the N-terminal domain has revealed a folding motif present in other protein families of unknown function and should lead to new insights regarding ways in which Lon interacts with substrates or other cellular factors. These first glimpses of the structure of Lon are heralding an exciting new era of research on this ancient family of proteases.

Keywords: AAA⁺ protein; Lon protease; ATP-dependent protease; Ser-Lys dyad; LonA and LonB subfamilies; domains; crystal structure

CiteULike

Connotea

Del.icio.us

Digg

Reddit

Technorati

This article has been cited by other articles:

				M. Chruszcz, A. Wlodawer, and W. Minor Determination of Protein Structures--A Series of Fortunate Events Biophys. J., July 1, 2008; 95(1): 1 - 9. [Abstract] [Full Text] [PDF]