SMc01553 is the sixth acyl carrier protein in Sinorhizobium meliloti 1021.
Acyl carrier proteins (ACPs) are required for the transfer of acyl intermediates during fatty acid and polyketide syntheses. In Sinorhizobium meliloti 1021 there are five known ACPs: AcpP, NodF, AcpXL, the ACP domain in RkpA and SMb20651. The genome sequence of S. meliloti 1021 also reveals the ORF SMc01553, annotated as a putative ACP. smc01553 is part of a 6.6 kb DNA region that is duplicated in the chromosome and in the pSymb plasmid, the result of a recent duplication event. SMc01553 overexpressed in Escherichia coli was labelled in vivo with [(3)H]beta-alanine, a biosynthetic building block of the 4'-phosphopantetheine prosthetic group of ACPs. The purified SMc01553 was modified with 4'-phosphopantetheine in the presence of S. meliloti holo-ACP synthase, and this modification resulted in a major conformational change of the protein structure, since the holo-form runs faster in native PAGE than the apo-form. SMc01553 could not be loaded with a malonyl group by malonyl-CoA-ACP transacylase from S. meliloti. Using RT-PCR we could show the presence of mRNA for SMc01553 and of the duplicated ORF SMb22007 in cultures of S. meliloti. However, a mutant in which the two duplicated regions were deleted did not show any different phenotype with respect to the wild-type in the free-living or symbiotic lifestyle.
Dávila-Martínez
Yadira
Y
Programa de Ecología Genómica, Centro de Ciencias Genómicas, Universidad Nacional Autónoma de México, Apdo. Postal 565-A, Cuernavaca, Morelos, C.P. 62251, Mexico.
Ramos-Vega
Ana Laura
AL
Programa de Ecología Genómica, Centro de Ciencias Genómicas, Universidad Nacional Autónoma de México, Apdo. Postal 565-A, Cuernavaca, Morelos, C.P. 62251, Mexico.
Contreras-Martínez
Sandra
S
Programa de Genómica Funcional de Procariontes, Centro de Ciencias Genómicas, Universidad Nacional Autónoma de México, Apdo. Postal 565-A, Cuernavaca, Morelos, C.P. 62251, Mexico.
Encarnación
Sergio
S
Programa de Genómica Funcional de Procariontes, Centro de Ciencias Genómicas, Universidad Nacional Autónoma de México, Apdo. Postal 565-A, Cuernavaca, Morelos, C.P. 62251, Mexico.
Geiger
Otto
O
Programa de Ecología Genómica, Centro de Ciencias Genómicas, Universidad Nacional Autónoma de México, Apdo. Postal 565-A, Cuernavaca, Morelos, C.P. 62251, Mexico.
López-Lara
Isabel M
IM
Programa de Ecología Genómica, Centro de Ciencias Genómicas, Universidad Nacional Autónoma de México, Apdo. Postal 565-A, Cuernavaca, Morelos, C.P. 62251, Mexico.
D000213:Acyl Carrier Protein / Q000235:genetics / Q000378:metabolism*; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D010204:Pantetheine / Q000031:analogs & derivatives; D017433:Protein Structure, Secondary; D012329:RNA, Bacterial / Q000378:metabolism; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016962:Sinorhizobium meliloti / Q000235:genetics* / Q000378:metabolism
D000213:Acyl Carrier Protein; D001426:Bacterial Proteins; D012329:RNA, Bacterial; D011994:Recombinant Proteins; D010204:Pantetheine; C003129:4'-phosphopantetheine