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: 9937

#XL - T Zoology

Intracellular bacterial

Intracellular bacterial infections tend to induce a cell-mediated immune response, specifically DTH. 

In this response, cytokines secreted by CD4+ T cells are important—most notably IFN-ϒ, which activates macrophages.

TLS Online TPP Program

#Id: 9938

#XL - T Zoology

Host immune responses and bacterial evasion mechanisms

TLS Online TPP Program

#Id: 9939

#XL - T Zoology

Tuberculosis

Tuberculosis, caused by Mycobacterium tuberculosis.

Pulmonary infection usually results from inhalation of small droplets of respiratory secretions containing a few bacilli.

TLS Online TPP Program

#Id: 9940

#XL - T Zoology

The inhaled bacilli are ingested by alveolar macrophages in the lung and inhibiting formation of phagolysosomes

CD4+ T cells are activated within 2 to 6 weeks after infection.

TLS Online TPP Program

#Id: 9941

#XL - T Zoology

These cells wall off the organism inside a granuloma called a tubercle. The localized concentrations of lysosomal enzymes in these granulomas can cause extensive tissue necrosis.

TLS Online TPP Program

#Id: 9942

#XL - T Zoology

Diphtheria

Natural infection with C. diphtheriae occurs only in humans and is spread by respiratory droplets. 

The organism colonizes the nasopharyngeal tract and causes little tissue damage, with only a mild inflammatory reaction.