Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
47
pubmed:dateCreated
2003-11-17
pubmed:abstractText
Complete oxidation of carbohydrates to CO2 is considered to be the exclusive property of the ubiquitous tricarboxylic acid cycle, the central process in cellular energy metabolism of aerobic organisms. Based on metabolism-wide in vivo quantification of intracellular carbon fluxes, we describe here complete oxidation of carbohydrates via the novel P-enolpyruvate (PEP)-glyoxylate cycle, in which two PEP molecules are oxidized by means of acetyl coenzyme A, citrate, glyoxylate, and oxaloacetate to CO2, and one PEP is regenerated. Key reactions are the constituents of the glyoxylate shunt and PEP carboxykinase, whose conjoint operation in this bi-functional catabolic and anabolic cycle is in sharp contrast to their generally recognized functions in anaplerosis and gluconeogenesis, respectively. Parallel operation of the PEP-glyoxylate cycle and the tricarboxylic acid cycle was identified in the bacterium Escherichia coli under conditions of glucose hunger in a slow-growing continuous culture. Because the PEP-glyoxylate cycle was also active in glucose excess batch cultures of an NADPH-overproducing phosphoglucose isomerase mutant, one function of this new central pathway may be the decoupling of catabolism from NADPH formation that would otherwise occur in the tricarboxylic acid cycle.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
21
pubmed:volume
278
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
46446-51
pubmed:meshHeading
pubmed:year
2003
pubmed:articleTitle
A novel metabolic cycle catalyzes glucose oxidation and anaplerosis in hungry Escherichia coli.
pubmed:affiliation
Institute of Biotechnology, ETH Zürich, CH-8093 Zürich, Switzerland.
pubmed:publicationType
Journal Article