Table of Contents
What is a energy carrier cells use to transport high-energy electrons?
NADP+ (nicotinamide adenine dinucleotide phosphate) – carrier molecule that transfers high-energy electrons from chlorophyll to other molecules. It accepts and holds two high-energy electrons and a hydrogen to become NADPH.
What is NADPH responsible for?
NADPH is an energy-carrying molecule produced in the first stage of photosynthesis. It provides energy to fuel the Calvin cycle in the second stage of photosynthesis.
What carries high energy electrons?
High-energy electrons are released from NADH and FADH2, and they move along electron transport chains, like those used in photosynthesis. The electron transport chains are on the inner membrane of the mitochondrion. As the high-energy electrons are transported along the chains, some of their energy is captured.
What transports high energy electrons?
When electrons in chlorophyll absorb sunlight, the electrons gain a great deal of energy. Cells use electron carriers to transport these high-energy electrons from chlorophyll to other molecules.
What cellular enzyme produces NADPH?
glucose-6-phosphate dehydrogenase
Four enzymes produce NADPH: glucose-6-phosphate dehydrogenase (G6PD), the key regulatory enzyme of the pentose phosphate pathway, phosphogluconate dehydrogenase (PGD), the third enzyme of that pathway, malate dehydrogenase (MDH), and isocitrate dehydrogenase (ICDH).
What is the energy in transfer of a phosphate group?
What is the energy in transfer of a phosphate group? ATP hydrolysis is one of the quintessential reactions of the cell and has led some to christen the ATP synthase, which adds phosphate groups onto ADP, as “the world’s second most important molecule” (DNA arguably being the first).
What happens when a phosphate is added to a protein?
For example, a given protein might have several stable configurations, with one of those states having an overall lower free energy. The addition of a charged group such as a phosphate can then tip the free energy balance such that now a different conformation has the lowest free energy.
How is the energy released when a phosphate group bond dissociates?
In shifting from phosphate groups as tags on proteins to their role as energy carriers it is essential to understand that the amount of energy released when a phosphate group bond dissociates depends on the compound it is attached to. Common metabolites exhibit a big difference in the energy released upon hydrolysis of their phosphate group.
How is the phosphate group used in signal transduction?
For example, as the main ingredient of signal transduction, ATP hydrolysis to ADP and inorganic phosphate (breaking a bond between two phosphates) is used in order to phosphorylate amino acids in proteins. In the most common cases, those of phosphorylation on serine and threonine, the phosphate group reacts with a hydroxyl group (-OH).