toxic proteins drive brazil-italy connections · célia regina carlini laboratory of toxic proteins...

Toxic proteins drive Brazil-Italy connections

Célia Regina Carlini

Laboratory of Toxic Proteins

Dept. Biophysics & Center of Biotechnology

Universidade Federal do Rio Grande do Sul

Porto Alegre, RS - Brazil

Rome , March 2012

Toxic proteins drive Brazil-Italy connections - Célia R. Carlini - Rome, March 2012

Toxic proteins in plants: role in defense mechanisms – abundant in seeds

– lethal to vertebrates, invertebrates, bacteria, fungi, viruses

Classes of toxic proteins in plants:

Lectins: binding to carbohydrate

Ribosome-inactivating proteins (RIPs): inhibition of protein synthesis

Inhibitors of enzymes: anti-nutrional effects

Ureases: enzymatic and non-enzymatic effects

Etc…

Ribosome-inactivating proteins (RIPs): inhibition of protein synthesis

Ureases: enzymatic and non-enzymatic effects

Ribosome-inactivating proteins from plants:

Ricin (castor bean)

among the deadest toxins ever known

Abrin (Abrus precatorius)

�lethal dose in mammals: nanograms/kg

�Mechanism of action: enzymes that modify ribosomes causing

inhibition of protein synthesis

�Biological role: plant protection against viruses ?

�Potential applications:

�Chemical weapons – murder of KGB dissidents in London - Cold War

�Immunotoxins– “custom-made” drugs against cancer

– enzymatic portion of a RIP fused to

an anti-cancer immunoglobulin

– very active field of research

W-of-S: 3630 documents (140 in 2011-12)


A

Bricin

antibody

immunotoxin


200 documents W-of-S+ 7000 citations


Prof. Stirpe and Celia Carlini

September 2004


In 2004, I invited Prof. Stirpe to contribute a

review article on RIPs to a special issue of

Toxicon, which I edited.


Visit to Bologna, April 2006: Jorge Guimarães, Sybil Stirpe, Fiorenzo Stirpe and Célia Carlini


Ph.D. thesis of Lucia Bertholdo Vargas

RIPs are involved in plant protection against insects

CO + NH2 3NH3

H O2

2NH

O

CUrease

NH2 C

O

NH2

Urease


– non-enzymatic properties ?

2001 – first report by our group showing that ureases display several biological

properties not related to hydrolysis of urea

Helicobacter pyloriHelicobacter pyloriHelicobacter pyloriHelicobacter pylori

� Gram-negative bacterium, causative agent of gastritis, ulcers and stomach cancer

� 10%-15% of the bacterium total protein is urease; alkalinization of the stomach acidity due to

urease activity is important for gastric colonization by the bacteria.



XVI World Congress of International Society on Toxinology – Brazil, 2009

Célia Carlini

President of the Scientific Committee

Conferences:Prof. Cesare Montecucco

Universitá di Padova

Redi Award lecture - Clostridial Toxins

Prof. Fiorenzo Stirpe

Universitá di Bologna

Toxic and non-toxic RIPS

Dr. Marina De Bernard

Venetian Institute of Molecular Medicine

Helicobacter pylori toxins


Cesare Montecucco (Italy), Dulcineide Magalhães (Brazil), Célia Carlini (Brazil), Marina De

Bernard (Italy), Yoshio Yamaoka (USA)

XVI World Congress of the International Society on Toxinology

Recife, PE, Brazil – march 2009

Symposium: Helicobacter pylori Helicobacter pylori Helicobacter pylori Helicobacter pylori toxins


Dra. Marina De Bernard

Dr. Deiber Olivera-Severo

CAPES post-doctoral fellow

10 monthsBacterial and plant ureases

Ureases are nickel-dependent enzymes



Universitá di Bologna, September 2010:

Deiber Olivera-Severo, Rafael Real Guerra (3 months – Brazilian research grant), Celia Carlini, Barbara Zambelli, Francesco Musiani, Stefano Ciurli

On-going studies on Urease-derived peptides and accessory proteins

Thank you for your attention.

Visit us at www.ufrgs.br/laprotox

Laboratory of Toxic Proteins

UFRGS, Porto Alegre, RS

Brazil


toxic proteins drive brazil-italy connections · célia regina carlini laboratory of toxic proteins...

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