|Gene:||bioC||Accession Numbers: EG10119 (EcoCyc), b0777, ECK0766|
BioC is a methyltransferase involved in an early step of biotin biosynthesis [Del67, Rolfe68, Otsuka88]. It is thought to methylate the ω-carboxyl group of malonyl-[acp] to form a malonyl-[acp] methyl ester, which is recognized by the fatty acid synthetic enzymes [Lin10]. The methyl ester is processed via the fatty acid elongation cycle to give a pimeloyl-[acp] methyl ester, which is processed into pimelyl-[acp] by BioH [Lin10].
For a long time, neither the exact function of BioC nor the path to pimelate was understood. Lemoine et al. ([Lemoine96]) proposed that BioC may catalyze the stepwise condensation of malonyl-CoA by addition of acetate units. [ORegan89] cites unpublished results showing lack of growth of a bioC mutant on pimelate, but 13C tracing indicated that pimelate is not a precursor of biotin [Ifuku94]. The function of BioC was finally suggested in a 2010 study [Lin10]. Due to difficulties studying the E. coli enzyme in vitro, the biochemical function of the Bacillus cereus enzyme was determined; expression of this enzyme complements an E. coli bioC mutant [Lin12].
bioC mutants require biotin for growth [Del67] and appear to be blocked before the synthesis of pimeloyl-CoA [Cleary72]. Monomethyl esters of malonate, glutarate and pimelate allow growth of a bioC deletion mutant in the presence of a heterologous acyl-ACP synthetase that converts these compounds to ACP thioesters [Lin10].
Gene Citations: [Nath82]
|Map Position: [810,745 -> 811,500] (17.47 centisomes)||Length: 756 bp / 251 aa|
Molecular Weight of Polypeptide: 28.276 kD (from nucleotide sequence)
Unification Links: ASAP:ABE-0002648 , CGSC:957 , EchoBASE:EB0117 , EcoGene:EG10119 , EcoliWiki:b0777 , ModBase:P12999 , OU-Microarray:b0777 , PortEco:bioC , PR:PRO_000022223 , Pride:P12999 , Protein Model Portal:P12999 , RefSeq:NP_415298 , RegulonDB:EG10119 , SMR:P12999 , String:511145.b0777 , UniProt:P12999
In Paralogous Gene Group: 194 (13 members)
|Biological Process:||GO:0009102 - biotin biosynthetic process
[UniProtGOA12, UniProtGOA11a, GOA01a, Del67]
GO:0008152 - metabolic process [GOA01a]
GO:0032259 - methylation [UniProtGOA11a]
|Molecular Function:||GO:0010340 - carboxyl-O-methyltransferase activity
GO:0008168 - methyltransferase activity [UniProtGOA11a, GOA01a]
GO:0016740 - transferase activity [UniProtGOA11a]
|Cellular Component:||GO:0005829 - cytosol [DiazMejia09]|
|MultiFun Terms:||metabolism → biosynthesis of building blocks → cofactors, small molecule carriers → biotin|
|Growth Medium||Growth?||T (°C)||O2||pH||Osm/L||Growth Observations|
|LB enriched||Yes||37||Aerobic||6.95||Yes [Gerdes03, Comment 1]|
|LB Lennox||Yes||37||Aerobic||7||Yes [Baba06, Comment 2]|
|M9 medium with 0.4% glucose||No||37||Aerobic||7.2||0.27||No [Patrick07, Comment 3]|
|M9 medium with 1% glycerol||Yes||37||Aerobic||7.2||0.35||Yes [Joyce06, Comment 4]|
|MOPS medium with 0.4% glucose||Yes||37||Aerobic||7.2||0.22||Yes [Baba06, Comment 2]|
Enzymatic reaction of: malonyl-CoA methyltransferase (malonyl-[acp] methyltransferase)
EC Number: 18.104.22.168
The reaction direction shown, that is, A + B ↔ C + D versus C + D ↔ A + B, is in accordance with the Enzyme Commission system.
The reaction is physiologically favored in the direction shown.
10/20/97 Gene b0777 from Blattner lab Genbank (v. M52) entry merged into EcoCyc gene EG10119; confirmed by SwissProt match.
Baba06: Baba T, Ara T, Hasegawa M, Takai Y, Okumura Y, Baba M, Datsenko KA, Tomita M, Wanner BL, Mori H (2006). "Construction of Escherichia coli K-12 in-frame, single-gene knockout mutants: the Keio collection." Mol Syst Biol 2;2006.0008. PMID: 16738554
DiazMejia09: Diaz-Mejia JJ, Babu M, Emili A (2009). "Computational and experimental approaches to chart the Escherichia coli cell-envelope-associated proteome and interactome." FEMS Microbiol Rev 33(1);66-97. PMID: 19054114
Gerdes03: Gerdes SY, Scholle MD, Campbell JW, Balazsi G, Ravasz E, Daugherty MD, Somera AL, Kyrpides NC, Anderson I, Gelfand MS, Bhattacharya A, Kapatral V, D'Souza M, Baev MV, Grechkin Y, Mseeh F, Fonstein MY, Overbeek R, Barabasi AL, Oltvai ZN, Osterman AL (2003). "Experimental determination and system level analysis of essential genes in Escherichia coli MG1655." J Bacteriol 185(19);5673-84. PMID: 13129938
Ifuku94: Ifuku O, Miyaoka H, Koga N, Kishimoto J, Haze S, Wachi Y, Kajiwara M (1994). "Origin of carbon atoms of biotin. 13C-NMR studies on biotin biosynthesis in Escherichia coli." Eur J Biochem 220(2);585-91. PMID: 8125118
Joyce06: Joyce AR, Reed JL, White A, Edwards R, Osterman A, Baba T, Mori H, Lesely SA, Palsson BO, Agarwalla S (2006). "Experimental and computational assessment of conditionally essential genes in Escherichia coli." J Bacteriol 188(23);8259-71. PMID: 17012394
Otsuka88: Otsuka AJ, Buoncristiani MR, Howard PK, Flamm J, Johnson C, Yamamoto R, Uchida K, Cook C, Ruppert J, Matsuzaki J (1988). "The Escherichia coli biotin biosynthetic enzyme sequences predicted from the nucleotide sequence of the bio operon." J Biol Chem 263(36);19577-85. PMID: 3058702
AbdelHamid07a: Abdel-Hamid AM, Cronan JE (2007). "Coordinate expression of the acetyl coenzyme A carboxylase genes, accB and accC, is necessary for normal regulation of biotin synthesis in Escherichia coli." J Bacteriol 189(2);369-76. PMID: 17056747
©2014 SRI International, 333 Ravenswood Avenue, Menlo Park, CA 94025-3493