Disease relevance of ECs4127

• These phage are transfected into cells containing the plasmid encoding the BCCP-tagged protein [1].
• I report that expression of two mutant BCCPs lacking the thumb residues fails to restore growth and fatty acid synthesis to a temperature-sensitive E. coli strain that lacks BCCP when grown at nonpermissive temperature [2].
• The genetic organization of the Pseudomonas aeruginosa acetyl coenzyme A carboxylase (ACC) was investigated by cloning and characterizing a P. aeruginosa DNA fragment that complements an Escherichia coli strain with a conditional lethal mutation affecting the biotin carboxyl carrier protein (BCCP) subunit of ACC [3].

High impact information on ECs4127

• We also report that the N-terminal 30 or so residues of BCCP are responsible for the interaction of BCCP with BC and that the BC.BCCP complex is a substrate for biotinylation in vitro [4].
• The bacterial and chloroplast multisubunit acetyl-CoA carboxylases are unusual in that the highly symmetrical and conserved structure of the biotinoyl domain of the BCCP subunit is disrupted by a structured loop called the "thumb" that protrudes from body of the domain [5].
• E. coli BCCP is a member of a large family of protein domains modified by covalent attachment of biotin [6].
• In E. coli BCCP, this putative linker extends for about 42 residues with over half of the residues being proline or alanine [6].
• E. coli BCCP is a member of a large family of protein domains modified by covalent attachment of biotin to a specific lysine residue [2].

Chemical compound and disease context of ECs4127

• An unexpected result was that expression of a mutant BCCP in which the biotinylated lysine residue was substituted with cysteine was able to partially restore growth and fatty acid synthesis to the temperature-sensitive E. coli strain [2].
• The biotin carboxyl carrier protein (BCCP) component of Escherichia coli acetyl coenzyme A carboxylase and three peptides derived from BCCP by proteolytic digestion have been examined by circular dichroism spectroscopy [7].
• Recombinant Escherichia coli cells containing four genes for a phenylalanine ammonia-lyase, cinnamate/coumarate:CoA ligase, chalcone synthase, and chalcone isomerase, in addition to the acetyl-CoA carboxylase, have been established for efficient production of (2S)-naringenin from tyrosine and (2S)-pinocembrin from phenylalanine [8].

Biological context of ECs4127

• The protein of interest is "tagged" with a portion of the biotin carboxylase carrier protein (BCCP), encoded on a specially constructed plasmid, so that it becomes biotinylated in vivo [1].
• Translational fusions of the carboxyl-terminal 110 or 84 (but not 76) amino acids of BCCP to beta-galactosidase resulted in biotinated beta-galactosidase molecules and production of one such fusion was shown to result in derepression of the biotin biosynthetic operon [9].
• Amino-terminal amino acid sequencing of the purified BCCP protein confirmed the deduced amino acid sequence indicating that BCCP is a protein of atypical physical properties [9].
• This complementation was shown to be specific to BCCPs having native structure (excepting the biotinylated lysine) and is interpreted in terms of dimerization of the BCCP biotinyl domain during the ACC reaction [2].
• One hypothesis is that posttranslational modification of BCCP may result in conformational changes that regulate specific protein-protein interactions [10].

Anatomical context of ECs4127

• The four known components that constitute plastid ACCase are biotin carboxylase (BC), biotin carboxyl carrier protein (BCCP), and the alpha- and beta-subunits of carboxyltransferase (alpha- and beta-CT) [11].

Associations of ECs4127 with chemical compounds

• Therefore, the thumb structure is essential for the function of BCCP in the ACC reaction and provides a useful motif for distinguishing the biotinylated proteins of multisubunit ACCs from those of enzymes catalyzing other biotin-dependent reactions [2].
• However, the BCCP biotinyl domain differs from many of these proteins in that an eight-amino acid residue insertion is present upstream of the biotinylated lysine [2].
• BirA65-321 is, moreover, identical to intact BirA in catalysis of synthesis of bio-5'-AMP and in transfer of biotin from the adenylate to BCCP [12].
• Finally, the carboxy-biotinylated form of BCCP interacts with transcarboxylase in the transfer of the carboxylate to acetyl-CoA to form malonyl-CoA [13].
• BCCP carries a characteristic local sequence surrounding the canonical lysine residue, typically -M-K-M-. Archaeon Sulfolobus tokodaii is unique in that its BCCP has serine replaced for the methionine C-terminal to the lysine [14].

Analytical, diagnostic and therapeutic context of ECs4127

• By use of affinity chromatography using two different affinity tags it was shown that the complex consists of a two BCCP molecules per BC molecule [4].
• Here we used site-directed mutagenesis to investigate residues in BirA that may interact with E119 or E147 in BCCP [15].
• When assessed by gel filtration chromatography, PC-(BC) was found to exist either in dimers or monomers, depending on the protein concentration, while PC-(CT + BCCP) occurred in dimers for the most part [16].
• Although BCCP cannot be detected on sodium dodecyl sulfate-polyacrylamide gel electrophoresis, it appears as a prominent band in Western blot when probed with streptavidin peroxidase conjugate [17].

References