CeBiTec Colloquium
in cooperation with LABCON-OWL GmbH

 date

Monday, November 26th 2012, 17 c.t.

 location

G2-104, CeBiTec Building

 speaker

PD Dr. Gregor Grass

Institut für Mikrobiologie der Bundeswehr, München

title

Debunking and incapacitating your bacterial enemy: bioforensic reconnaissance in a drug-related anthrax outbreak and antimicrobial defense using copper surfaces

abstract Research of the Bundeswehr Institute of Microbiology is concerned with prophylaxis against highly pathogenic BSL-3 microorganisms and with bioforensic investigations of unusual outbreaks of lethal diseases. One topic related to prophylaxis against bacterial infection is the study of the antimicrobial mode-of-action exerted by metallic copper(alloy) surfaces. This research is expected to have considerable impact on the prevention of hospital-acquired and other surface-mediated infections in public places. Bacteria in direct contact to copper surfaces are inactivated within few minutes in a process called contact-killing. We are interested in elucidating the molecular mechanisms responsible for these antibacterial properties. For this, we used several bacterial models from Escherichia coli to Yersinia pestis and revealed that the germs are killed because of massive cell membrane damage. Genotoxicity is not the cause of death but DNA-damage rather follows the demise of the bacteria. Molecular details on the processes related to contact-killing of microbes by metallic copper surfaces will be presented. Anthrax is a lethal zoonotic disease and endospores of the causative agent, Bacillus anthracis, had been used in the past as a bioterrorist weapons and in state-sponsored biowarfare programs. Recently, more than one hundred cases of injectional anthrax in heroin consumers have been observed in several European countries resulting in 22 deaths. This unusual manifestation of the disease is of great concern because of its high casualty-rate and because the source of the pathogen remains obscure. Also, it is unknown if the origin of the heroin-associated anthrax-endospores was a natural, unintentional or intentional (bioterrorism) contamination. In order to trace-back the source of the bacteria, we conducted a molecular-genetic bioforensic investigation beginning with two Bavarian cases in June 2012. Comparative analysis of several independent genomic markers between recent drug-related and endemic strains of B. anthracis from all over the world revealed a possible non-terroristic connection of the endospore-contamination to international drug-trafficking.
 host

Dr. Jörn Kalinowski
Dr. Carsten Tiemann (LABCON-OWL GmbH)