Mechanism of action of pertussis toxin is all except:
Ans. is 'a' i.e., Act by ADP ribosylation of GI subunitRef: (Harrison, 19th/e, p. 1021 and Ananthanarayan, 9th/e, p. 333)Pertussis toxin (PT) - Most imp. Virulence factor composed of 2 subunits (A and B) like cholera toxin. A subunit having ADP ribosylation activity of G protein - | cAMP - responsible for several biological effects like T cell mitogeni- city, Hemagglutination, Adhesion to respiratory ciliated cells, induction of leukocytosis, histamine sensitizer.
Act by ADP ribosylation of GI subunit
Increase in calcium
Act by decreasing GTP
B subunit having ADP ribosylating activity
Bacteria