A mutational analysis of residues in cholera toxin A1 necessary for interaction with its substrate, the stimulatory G protein Gsα

Toxins
Michael G JoblingRandall K Holmes

Abstract

Pathogenesis of cholera diarrhea requires cholera toxin (CT)-mediated adenosine diphosphate (ADP)-ribosylation of stimulatory G protein (Gsα) in enterocytes. CT is an AB5 toxin with an inactive CTA1 domain linked via CTA2 to a pentameric receptor-binding B subunit. Allosterically activated CTA1 fragment in complex with NAD+ and GTP-bound ADP-ribosylation factor 6 (ARF6-GTP) differs conformationally from the CTA1 domain in holotoxin. A surface-exposed knob and a short α-helix (formed, respectively, by rearranging "active-site" and "activation" loops in inactive CTA1) and an ADP ribosylating turn-turn (ARTT) motif, all located near the CTA1 catalytic site, were evaluated for possible roles in recognizing Gsα. CT variants with one, two or three alanine substitutions at surface-exposed residues within these CTA1 motifs were tested for assembly into holotoxin and ADP-ribosylating activity against Gsα and diethylamino-(benzylidineamino)-guanidine (DEABAG), a small substrate predicted to fit into the CTA1 active site). Variants with single alanine substitutions at H55, R67, L71, S78, or D109 had nearly wild-type activity with DEABAG but significantly decreased activity with Gsα, suggesting that the corresponding residues in native CTA...Continue Reading

References

Jul 1, 1978·Proceedings of the National Academy of Sciences of the United States of America·D M Gill, R Meren
Nov 1, 1989·Journal of Clinical Microbiology·J NarayananD J Graves
Dec 15, 1989·Biochemical and Biophysical Research Communications·F J Klinz, T Costa
Aug 1, 1987·Proceedings of the National Academy of Sciences of the United States of America·S C TsaiM Vaughan
Dec 6, 2000·Proceedings of the National Academy of Sciences of the United States of America·M G Jobling, R K Holmes
Jan 5, 2002·Methods in Enzymology·Shui-Zhong Yan, Wei-Jen Tang
Jan 24, 2004·Lancet·David A SackA K Siddique
May 20, 2004·International Journal of Medical Microbiology : IJMM·Wayne I Lencer
Aug 16, 2005·Science·Claire J O'NealWim G J Hol
Mar 29, 2008·Protein Science : a Publication of the Protein Society·Julie MénétreyEnrico A Stura
May 21, 2008·Proceedings of the National Academy of Sciences of the United States of America·Hideaki TsugeJun Sakurai
Jun 4, 2010·Amino Acids·Susann WolfJens Pietzsch
May 25, 2011·Proceedings of the National Academy of Sciences of the United States of America·Ned Van EpsWayne L Hubbell
Jul 21, 2011·Nature·Søren G F RasmussenBrian K Kobilka
Sep 15, 2011·Proceedings of the National Academy of Sciences of the United States of America·Gerwin H WestfieldGeorgios Skiniotis
Feb 6, 2013·Proceedings of the National Academy of Sciences of the United States of America·Toshiharu TsurumuraHideaki Tsuge

❮ Previous
Next ❯

Citations

Nov 20, 2015·Basic & Clinical Pharmacology & Toxicology·Douglas S CostaJand Venes R Medeiros
Nov 10, 2016·PloS One·Patrick CherubinKen Teter
Sep 2, 2020·Journal of Bacteriology·Abby FrederickDean A Rowe-Magnus

❮ Previous
Next ❯

Methods Mentioned

BETA
two-hybrid
ribosylation
restriction
PCR
ion-exchange chromatography
electrophoresis

Related Concepts

Trending Feeds

COVID-19

Coronaviruses encompass a large family of viruses that cause the common cold as well as more serious diseases, such as the ongoing outbreak of coronavirus disease 2019 (COVID-19; formally known as 2019-nCoV). Coronaviruses can spread from animals to humans; symptoms include fever, cough, shortness of breath, and breathing difficulties; in more severe cases, infection can lead to death. This feed covers recent research on COVID-19.

Blastomycosis

Blastomycosis fungal infections spread through inhaling Blastomyces dermatitidis spores. Discover the latest research on blastomycosis fungal infections here.

Nuclear Pore Complex in ALS/FTD

Alterations in nucleocytoplasmic transport, controlled by the nuclear pore complex, may be involved in the pathomechanism underlying multiple neurodegenerative diseases including Amyotrophic Lateral Sclerosis and Frontotemporal Dementia. Here is the latest research on the nuclear pore complex in ALS and FTD.

Applications of Molecular Barcoding

The concept of molecular barcoding is that each original DNA or RNA molecule is attached to a unique sequence barcode. Sequence reads having different barcodes represent different original molecules, while sequence reads having the same barcode are results of PCR duplication from one original molecule. Discover the latest research on molecular barcoding here.

Chronic Fatigue Syndrome

Chronic fatigue syndrome is a disease characterized by unexplained disabling fatigue; the pathology of which is incompletely understood. Discover the latest research on chronic fatigue syndrome here.

Evolution of Pluripotency

Pluripotency refers to the ability of a cell to develop into three primary germ cell layers of the embryo. This feed focuses on the mechanisms that underlie the evolution of pluripotency. Here is the latest research.

Position Effect Variegation

Position Effect Variagation occurs when a gene is inactivated due to its positioning near heterochromatic regions within a chromosome. Discover the latest research on Position Effect Variagation here.

STING Receptor Agonists

Stimulator of IFN genes (STING) are a group of transmembrane proteins that are involved in the induction of type I interferon that is important in the innate immune response. The stimulation of STING has been an active area of research in the treatment of cancer and infectious diseases. Here is the latest research on STING receptor agonists.

Microbicide

Microbicides are products that can be applied to vaginal or rectal mucosal surfaces with the goal of preventing, or at least significantly reducing, the transmission of sexually transmitted infections. Here is the latest research on microbicides.