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 Pfennig, F. Articles by Keller, U. Search for Related Content PubMed PubMed Citation Articles by Pfennig, F. Articles by Keller, U. Social Bookmarking                      What's this?

J Biol Chem, Vol. 274, Issue 18, 12508-12516, April 30, 1999

Molecular Characterization of the Genes of Actinomycin Synthetase I and of a 4-Methyl-3-hydroxyanthranilic Acid Carrier Protein Involved in the Assembly of the Acylpeptide Chain of Actinomycin in Streptomyces

From the Max-Volmer-Institut für Biophysikalische Chemie und Biochemie, Fachgebiet Biochemie und Molekulare Biologie, Technische Universität Berlin, Franklinstrasse 29, D-10587 Berlin-Charlottenburg, Germany

Actinomycin synthetase I (ACMS I) activates 4-methyl-3-hydroxyanthranilic acid, the precursor of the chromophoric moiety of the actinomycin, as adenylate. The gene acmA of ACMS I was identified upstream of the genes acmB and acmC encoding the two peptide synthetases ACMS II and ACMS III, respectively, which assemble the pentapeptide lactone rings of the antibiotic. Sequence analysis and expression of acmA in Streptomyces lividans as enzymatically active hexa-His-fusion confirmed the acmA gene product to be ACMS I. An open reading frame of 234 base pairs (acmD), which encodes a 78-amino acid protein with similarity to various acyl carrier proteins, is located downstream of acmA. The acmD gene was expressed in Escherichia coli as hexa-His-fusion protein (Acm acyl carrier protein (AcmACP)). ACMS I in the presence of ATP acylated the purified AcmACP with radioactive p-toluic acid, used as substrate in place of 4-MHA. Only 10% of the AcmACP from E. coli was acylated, suggesting insufficient modification with 4'-phosphopantetheine cofactor. Incubation of this AcmACP with a holo-ACP synthase and coenzyme A quantitatively established the holo-form of AcmACP. Enzyme assays in the presence of ACMS II showed that toluyl-AcmACP directly acylated the thioester-bound threonine on ACMS II. Thus, AcmACP is a 4-MHA carrier protein in the peptide chain initiation of actinomycin synthesis.

CiteULike

Complore

Connotea

Del.icio.us

Digg

Reddit

Technorati

This article has been cited by other articles:

				G. Schmoock, F. Pfennig, J. Jewiarz, W. Schlumbohm, W. Laubinger, F. Schauwecker, and U. Keller Functional Cross-talk between Fatty Acid Synthesis and Nonribosomal Peptide Synthesis in Quinoxaline Antibiotic-producing Streptomycetes J. Biol. Chem., February 11, 2005; 280(6): 4339 - 4349. [Abstract] [Full Text] [PDF]

				J. Martinez-Gonzalez, B. Raposo, C. Rodriguez, and L. Badimon 3-Hydroxy-3-Methylglutaryl Coenzyme A Reductase Inhibition Prevents Endothelial NO Synthase Downregulation by Atherogenic Levels of Native LDLs : Balance Between Transcriptional and Posttranscriptional Regulation Arterioscler. Thromb. Vasc. Biol., May 1, 2001; 21(5): 804 - 809. [Abstract] [Full Text] [PDF]