Simultaneous occurrence of two different glyceraldehyde-3-phosphate dehydrogenases in heterocystous N(2)-fixing cyanobacteria.
Enzyme activity determinations and Western and Northern blot analyses have shown the presence of two catalytically different glyceraldehyde-3-phosphate dehydrogenases (GAPDH) in both vegetative cells and heterocysts of several N(2)-fixing Anabaena strains: (a) the gap2-encoded NAD(P)-dependent GAPDH2 (EC 1.2.1.59), the enzyme involved in the photosynthetic carbon assimilation pathway, which is present at higher levels in vegetative cells, and (b) the gap3-encoded NAD-dependent GAPDH3 (EC 1.2.1.12), presumably involved in carbohydrate anabolism and catabolism, which is the predominant GAPDH in heterocysts. In contrast, the gap1-encoded GAPDH1, which is the other NAD-dependent cyanobacterial GAPDH, is virtually absent in both cell types. These findings are discussed in the context of carbon metabolism of heterocystous N(2)-fixing cyanobacteria.
Valverde
F
F
Instituto de Bioquímica Vegetal y Fotosíntesis, Universidad de Sevilla-CSIC, Seville, Spain.
Peleato
M L
ML
Fillat
M F
MF
Gómez-Moreno
C
C
Losada
M
M
Serrano
A
A
D017033:Anabaena / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development; D001483:Base Sequence; D015152:Blotting, Northern; D015153:Blotting, Western; D017931:DNA Primers / Q000235:genetics; D005798:Genes, Bacterial; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism*; D007527:Isoenzymes / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D009243:NAD / Q000378:metabolism; D009586:Nitrogen Fixation; D012329:RNA, Bacterial / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism
D017931:DNA Primers; D007527:Isoenzymes; D012329:RNA, Bacterial; D012333:RNA, Messenger; D009243:NAD; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases