Nitrite reductase

Nitrite (NO2-) is a highly reactive, potentially toxic ion.

Plant cells immediately transport the nitrite into chloroplasts or plastids.

The enzyme nitrite reductase reduces nitrite to ammonium.

Leaf chloroplasts and root plastids contain different forms of nitrite reductase.

Each polypeptide contains two prosthetic groups, an iron-sulfur group and a specialized heme.

NO3-, high sucrose conc, and light induce the transcription of nitrite reductase mRNA.

Asparagine and glutamine repress the induction.

TLS Online TPP Program

#Id: 9297

#XL - Q Biochemistry

Nitrite reductase

Nitrite (NO2-) is a highly reactive, potentially toxic ion.

Plant cells immediately transport the nitrite into chloroplasts or plastids.

The enzyme nitrite reductase reduces nitrite to ammonium.

Leaf chloroplasts and root plastids contain different forms of nitrite reductase.

Each polypeptide contains two prosthetic groups, an iron-sulfur group and a specialized heme.

NO3-, high sucrose conc, and light induce the transcription of nitrite reductase mRNA.

Asparagine and glutamine repress the induction.

TLS Online TPP Program

#Id: 9297

#XL - S Microbiology

Nitrite reductase

Nitrite (NO2-) is a highly reactive, potentially toxic ion.

Plant cells immediately transport the nitrite into chloroplasts or plastids.

The enzyme nitrite reductase reduces nitrite to ammonium.

Leaf chloroplasts and root plastids contain different forms of nitrite reductase.

Each polypeptide contains two prosthetic groups, an iron-sulfur group and a specialized heme.

NO3-, high sucrose conc, and light induce the transcription of nitrite reductase mRNA.

Asparagine and glutamine repress the induction.

TLS Online TPP Program

#Id: 8648

#XL - T Zoology

During exit from mitosis and G1, 

Cdh1 is de-phosphorylated and APC/Ccdh1 is active.

TLS Online TPP Program

#Id: 8649

#XL - T Zoology

During S phase and mitosis, 

Cdh1 is phosphorylated, Cdh1 dissociates from APC/C, and APC/C becomes inactive.

TLS Online TPP Program

#Id: 8650

#XL - T Zoology

G1/S phase CDKs phosphorylate Cdh1 at the 

G1-S phase transition

TLS Online TPP Program

#Id: 8651

#XL - T Zoology

S phase cyclin-CDK accumulates in late G1 , they are immediately inactivated by binding of a CKI called Sic1

TLS Online TPP Program

#Id: 8652

#XL - T Zoology

TLS Online TPP Program

#Id: 8653

#XL - T Zoology

Degradation of Sic1 is induced by its phosphorylation by G1/S phase CDKs.