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: 9339

#XL - T Zoology

TGF-β is synthesized with a, 

250-residue N-terminal prodomain

∼110-residue C-terminal TGF-β domain

TLS Online TPP Program

#Id: 9340

#XL - T Zoology

N-terminal prodomain is required for proper folding and dimerization of the C-terminal TGF-β domain.

TLS Online TPP Program

#Id: 9341

#XL - T Zoology

TGF-β latency

In the Golgi prodomain is proteolytically cleaved from the mature growth factor but remains noncovalently attached even after secretion.

TLS Online TPP Program

#Id: 9342

#XL - T Zoology

Prodomain prevents the latent TGF-β 

from binding to a cell-surface receptor.

TLS Online TPP Program

#Id: 9343

#XL - T Zoology

Prodomain forms disulfide linkages that localize the latent TGF-β to the surface of the secreting cell (GARP), to a nearby cell, or to the extracellular matrix (LTBP).

TLS Online TPP Program

#Id: 9345

#XL - T Zoology

TGF-β activation

By cytoskeletal force transmitted by integrins