Some elements exist naturally as molecules. For example, hydrogen and oxygen exist as two-atom molecules.

TLS Online TPP Program

#Id: 9018

#Unit 6. System Physiology – Plant

When dark‐treated chloroplasts are exposed to light

activate enzymes of the Calvin–Benson cycle that require Mg2+ for catalysis and are more active at pH 8 than at pH 7 for STROMA

TLS Online TPP Program

#Id: 9019

#Unit 6. System Physiology – Plant

Five pivotal enzymes are regulated by Ferredoxin–thioredoxin Fd-Thrx system

TLS Online TPP Program

#Id: 9020

#Unit 6. System Physiology – Plant

Thioredoxins occur in multiple forms and have conserved structures to interact with target enzymes

TLS Online TPP Program

#Id: 9021

#Unit 6. System Physiology – Plant

There are Seven different types of thioredoxin in cells, Trx f, m, x, y, and z are located in the chloroplasts, o in mitochondria, and h in the cytosol, endoplasmic reticulum, and plasma membrane.

TLS Online TPP Program

#Id: 9022

#Unit 6. System Physiology – Plant

Trx proteins are characterized by a canonical disulfide active site consisting of Cys‐Gly‐Pro‐ Cys

TLS Online TPP Program

#Id: 9023

#Unit 6. System Physiology – Plant

Trx have common tertiary structure called the thioredoxin fold, which consists of five antiparallel beta sheets sandwiched between three alpha helices.