It was also observed that the restriction of the gas exchange activity was so drastic that the reduction of the photosynthetic activity in the higher levels of salinity promoted an increase of the internal [CO.sub.2] concentration, as observed in the [A.sub.3] management plants, probably due to the malfunction of the activity of the enzyme Ribulose
1,5-bisphosphate carboxylase oxygenase (RuBisCO) (Fugura 7D).
1,5-bisphosphate carboxylase/oxygenase), the most abundant enzyme in nature and responsible for C[O.sub.2] fixation by photosynthetic organisms, is a complex protein composed from eight identical large subunits ([M.sub.r] 53000) that are encoded in the chloroplast genome, each one with catalytic site and eight identical small subunits ([M.sub.r] 14000) that are encoded in the nuclear genome .
In maize, two distinct ribulose
1,5-bisphosphate carboxylase/ oxygenaseactivase transcripts have different day/night patterns of expression.
[28.] Goloubinoff P, Christeller JT, Gatenby AA, Lorimer GH Reconstitution of active dimeric ribulose
bisphosphate carboxylase from an unfoleded state depends on two chaperonin proteins and Mg-ATP.
TABLE 1: Expression of Symbiodinium ribulose
, 1-5, bisphosphate carboxylase/oxygenase large subunit (rbcL), photosy Gene Function Results from prior Results discussed works herein rbcL Photosynthesis Higher at variable temperature (a) psI Photosynthesis Higher at variable Negatively correlated temperature (a) with [F.sub.v]/ Higher [F.sub.M.sup.b] pgpase Photosynthesis Higher at variable Positively correlated temperature (a) with ps1 (b) apxl Stress response Positively correlated with pgpase (b) (a) See .
The effect of ethylene on photosynthesis also has influence on plant water use efficiency and associated with higher Rubisco (ribulose
1,5 bisphosphate carboxylase) activity or rate of electron transport (Van den Boogard et al., 1996).
Quando atua como carboxilase, o C[O.sub.2] reage com a ribulose
1,5-bisfosfato formando duas moleculas de 3-fosfoglicerato.
The oxidative branch of the PPP converts glucose into ribulose
and generates the reducing force NADPH, which is critical in defense against oxidative stress, lipid synthesis, and many other anabolic reactions.
Rubisco large subunit: The large subunit (53kDa) of Ribulose
1,5-bis phosphate carboxylase/oxygenase that functions in the dark reaction of photosynthesis is the most abundant protein.
Results: Proteins of plant origin in Ankaferd[R] were NADP-dependent-malic enzyme, ribulose
bisphosphate-carboxylase-large chain, maturase K, ATP synthase subunit-beta, ATP synthase subunit-alpha, chalcone-flavanone isomerase-1, chalcone-flavanone isomerase-2, and actin-depolymerizing factor.
As shown in Figure 7-3, C[O.sub.2] is added to a five-carbon compound called ribulose