Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2004-6-28
pubmed:abstractText
An integrated study of cell growth characteristics, enzyme activities and protein expression patterns was carried out to investigate how the central metabolism of Escherichia coli changes upon knockout of the isocitrate dehydrogenase (ICDH) gene (icd) in the tricarboxylic acid cycle. Deletion of the icd gene led to reduced specific growth rate and reduced specific glucose consumption rate. The reduced specific growth rate in the icd mutant was due mainly to the lower intracellular ATP/ADP ratio as well as to the lower NADPH/NADP(+) ratio compared with those in the parent strain. However, the specific carbon dioxide evolution rate was found to be higher in the icd mutant strain compared to the parent E. coli. This may be due to the higher activity of 6-phosphogluconate dehydrogenase, phosphoenol pyruvate carboxykinase and NADP(+)-dependent malic enzymes. The glyoxylate pathway was also utilized, as evidenced by the significant upregulation of isocitrate lyase and malate synthase activity in the icd mutant E. coli. The appearance of the glyoxylate pathway caused lower acetate production. Of 21 proteins showing altered expression levels, 17 were successfully identified with the aid of MALDI-TOF mass spectrometry. The results showed that the abolition of ICDH activity significantly affected the respiratory system and electron transport chain, as evidenced by the significant downregulation of proteins encoded by the genes nuoE, nuoH, cydA and cyoA in icd mutant E. coli compared to the parent.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0175-7598
pubmed:author
pubmed:issnType
Print
pubmed:volume
65
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
84-96
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2004
pubmed:articleTitle
Metabolic regulation analysis of icd-gene knockout Escherichia coli based on 2D electrophoresis with MALDI-TOF mass spectrometry and enzyme activity measurements.
pubmed:affiliation
Department of Biochemical Engineering and Science, Kyushu Institute of Technology, Iizuka 820-8502, Fukuoka, Japan.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't