Giardia intestinalis escapes oxidative stress by colonizing the small intestine: A molecular hypothesis. - RIIP - Réseau International des Instituts Pasteur Access content directly
Journal Articles IUBMB Life Year : 2010

Giardia intestinalis escapes oxidative stress by colonizing the small intestine: A molecular hypothesis.

Abstract

Giardia intestinalis is the microaerophilic protozoon causing giardiasis, a common infectious intestinal disease. Giardia possesses an O(2) -scavenging activity likely essential for survival in the host. We report that Giardia trophozoites express the O(2) -detoxifying flavodiiron protein (FDP), detected by immunoblotting, and are able to reduce O(2) to H(2) O rapidly (∼3 μM O(2) × min × 10(6) cells at 37 °C) and with high affinity (C(50) = 3.4 ± 0.7 μM O(2)). Following a short-term (minutes) exposure to H(2) O(2) ≥ 100 μM, the O(2) consumption by the parasites is irreversibly impaired, and the FDP undergoes a degradation, prevented by the proteasome-inhibitor MG132. Instead, H(2) O(2) does not cause degradation or inactivation of the isolated FDP. On the basis of the elevated susceptibility of Giardia to oxidative stress, we hypothesize that the parasite preferentially colonizes the small intestine since, compared with colon, it is characterized by a greater capacity for redox buffering and a lower propensity to oxidative stress.
Embargoed file
Embargoed file
Visibility date is undetermined
Loading...

Dates and versions

pasteur-00976014 , version 1 (09-04-2014)

Identifiers

Cite

Daniela Mastronicola, Alessandro Giuffrè, Fabrizio Testa, Antonella Mura, Elena Forte, et al.. Giardia intestinalis escapes oxidative stress by colonizing the small intestine: A molecular hypothesis.. IUBMB Life, 2010, 63 (1), pp.21-5. ⟨10.1002/iub.409⟩. ⟨pasteur-00976014⟩

Collections

RIIP
20 View
2 Download

Altmetric

Share

Gmail Facebook X LinkedIn More