Seasonal change in the balance between capacities of RuBP
carboxylation and RuBP
regeneration affects C[O.sub.2] response of photosynthesis in Polygonum cuspidatum.
Isso resulta na sintese de especies reativas de oxigenio (ROS), que danificam a enzima ATP sintase, retardando a sintese de ribulose 1,5-bifosfato (RuBP
) e havendo decrescimo na atividade da rubisco.
As shown in Figure 7-3, C[O.sub.2] is added to a five-carbon compound called ribulose diphosphate (RuBP
However, after many months of searching no 2-carbon compound was found, and the molecule eventually turned out to be a 5-carbon compound ribulose 1,5- bisphosphate (RuBP
) When C[O.sub.2] is combined with the 5-carbon molecule, it produces a very unstable 6-carbon intermediate, which immediately splits into two 3-carbon molecules, detected as PGA.
As we perform this musical in the class, the characters sing the lyrics (in italics below) and the following events, written under Directions for each segment, are acted out: The Story of the Calvin Cycle Here's the story of RuBP
Who was floating in the stroma on its own.
Assuming that four electrons are consumed per carboxylation or oxygenation of RuBP
by RubisCO and that electron flux to alternate sinks is negligible,
Most plants can get by with the simplest form of the Calvin cycle, in which a catalyst called RuBP
combines with [CO.sub.2] to create sugars.
In some plants, carbon is fixed when it reacts with the five-carbon sugar RuBP
(ribulose 1,5-diphosphate), forming two molecules of three-carbon ([C.sub.3]) sugars.
Sensitivity is due to the competition between carboxylation and oxygenation of ribulose bisphosphate (RuBP
) catalyzed by Ribulose-1,5-bisphosphate carboxylase-oxygenase (Rubisco) as described by Farquhar et al.
Although the higher foliar N concentrations might be associated with higher activity of RuBP
carboxylase, which should stimulate light-saturated (dark-reaction-limited) photosynthesis (Evans 1989), it is possible that much of the additional N in leaves was in the form of amino acids (Billow et al.
Variations in the light regime during growth typically cause changes in the rates of photosynthesis due to differences in the maximum carboxylation velocity of Rubisco (Vcmax.) and the maximum rate of regeneration of ribulose bisphosphate, RuBP
(Jmax.), which is dependent on transporting electrons, as well as differences in the rates of C[O.sub.2] diffusion into chloroplasts (AZEVEDO; MARENCO, 2012).
Previous studies noticed the reduction in the photosynthetic rate due to several coordinated events, such as stomatal closure, decreased ATP synthesis and RuBP
supply, and the reduced activity of photosynthetic enzymes (Lawlor and Cornic 2001; Chaves et al., 2003).