Linked Life Data

2040303

Source:http://linkedlifedata.com/resource/pubmed/id/2040303

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1991-7-10
pubmed:databankReference
pubmed:abstractText
Trypanosoma brucei contains two isoenzymes for glyceraldehyde-3-phosphate dehydrogenase: one enzyme resides in a microbody-like organelle, the glycosome; the other is found in the cytosol. Previously we have reported the characterization of the gene for the glycosomal enzyme [Michels, P. A. M., Poliszczak, A., Osinga, K. A., Misset, O., Van Beeumen, J., Wierenga, R. K., Borst, P. & Opperdoes, F. R. (1986) EMBO J. 5, 1049-1056]. Here we describe the cloning and analysis of the gene that codes for the cytosolic isoenzyme. The gene encodes a polypeptide of 330 amino acids, with a calculated molecular mass of 35440 Da. The two isoenzymes are only 55% identical. The cytosolic glyceraldehyde-3-phosphate dehydrogenase differs from the glycosomal enzyme in the following respects: (a) its subunit molecular mass is 3.4 kDa smaller due to the absence of insertions and a small C-terminal extension which are unique to the glycosomal protein; (b) the cytosolic enzyme has a lower pI (7.9, as compared to 9.3 for the glycosomal isoenzyme), which is due to a reduction in the excess of positively charged amino acids (the calculated net charges of the polypeptides are +2 and +11, respectively). We have compared the amino acid sequences of the two T. brucei glyceraldehyde-3-phosphate dehydrogenases, with 24 available sequences of the corresponding enzyme of other organisms from various phylogenetic groups. On the basis of this comparison an evolutionary tree was constructed. This analysis strongly supports the theory that T. brucei diverged early in evolution from the main eukaryotic branch of the phylogenetic tree. Further, two separate branches for the lineages leading to Trypanosoma are inferred from the amino acid sequences, suggesting that the genes for the two glyceraldehyde-3-phosphate dehydrogenases of the trypanosome are distantly related and must have been acquired independently by the trypanosomal ancestor. The branching determined with the glycosomal enzyme precedes that found with the cytosolic enzyme. The available data do not allow us to decide which of the two genes originally belonged to the trypanosome lineage and which entered the cell later by horizontal gene transfer.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0014-2956
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
198
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
421-8
pubmed:dateRevised
2010-11-18
pubmed:meshHeading
pubmed-meshheading:2040303-Amino Acid Sequence, pubmed-meshheading:2040303-Animals, pubmed-meshheading:2040303-Bacteria, pubmed-meshheading:2040303-Base Sequence, pubmed-meshheading:2040303-Biological Evolution, pubmed-meshheading:2040303-Cytosol, pubmed-meshheading:2040303-Genes, pubmed-meshheading:2040303-Genomic Library, pubmed-meshheading:2040303-Glyceraldehyde-3-Phosphate Dehydrogenases, pubmed-meshheading:2040303-Humans, pubmed-meshheading:2040303-Isoenzymes, pubmed-meshheading:2040303-Liver, pubmed-meshheading:2040303-Molecular Sequence Data, pubmed-meshheading:2040303-Organelles, pubmed-meshheading:2040303-Phylogeny, pubmed-meshheading:2040303-Rats, pubmed-meshheading:2040303-Restriction Mapping, pubmed-meshheading:2040303-Sequence Homology, Nucleic Acid, pubmed-meshheading:2040303-Trypanosoma brucei brucei
pubmed:year
1991
pubmed:articleTitle
The cytosolic and glycosomal isoenzymes of glyceraldehyde-3-phosphate dehydrogenase in Trypanosoma brucei have a distant evolutionary relationship.
pubmed:affiliation
International Institute of Cellular and Molecular Pathology, Research Unit for Tropical Diseases, Brussels, Belgium.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't