Alternative acetate production pathways in Chlamydomonas reinhardtii during dark anoxia and the dominant role of chloroplasts in fermentative acetate production.
Plant Cell
; 26(11): 4499-518, 2014 Nov.
Article
in En
| MEDLINE
| ID: mdl-25381350
ABSTRACT
Chlamydomonas reinhardtii insertion mutants disrupted for genes encoding acetate kinases (EC 2.7.2.1) (ACK1 and ACK2) and a phosphate acetyltransferase (EC 2.3.1.8) (PAT2, but not PAT1) were isolated to characterize fermentative acetate production. ACK1 and PAT2 were localized to chloroplasts, while ACK2 and PAT1 were shown to be in mitochondria. Characterization of the mutants showed that PAT2 and ACK1 activity in chloroplasts plays a dominant role (relative to ACK2 and PAT1 in mitochondria) in producing acetate under dark, anoxic conditions and, surprisingly, also suggested that Chlamydomonas has other pathways that generate acetate in the absence of ACK activity. We identified a number of proteins associated with alternative pathways for acetate production that are encoded on the Chlamydomonas genome. Furthermore, we observed that only modest alterations in the accumulation of fermentative products occurred in the ack1, ack2, and ack1 ack2 mutants, which contrasts with the substantial metabolite alterations described in strains devoid of other key fermentation enzymes.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Phosphate Acetyltransferase
/
Chloroplasts
/
Chlamydomonas reinhardtii
/
Acetate Kinase
/
Acetates
Language:
En
Journal:
Plant Cell
Journal subject:
BOTANICA
Year:
2014
Document type:
Article