XXII. BIOCHEMICKÝ ZJAZD - Jesseniova lekárska fakulta

Lectures
Assembly of BaCILLus suBTILIS SPOre COat: INvESTIGaTION of
prOTEIN-prOTEIN INTEraCTIONS aMONG THE SPOre COat prOTEINS
of BaCILLLUS SUBTILIS
Daniela Krajčíková 1 , Denisa Mullerová 1 , Wan Qiang 2 , Per Bullogh 2 ,
Jilin Tang 3 and Imrich Barák 1
1
Institute of Molecular Biology, Slovak Academy of Sciences, Bratislava, Slovakia;
2
Krebs Institute for Biomolecular Research, Department of Molecular Biology
and Biotechnology, University of Sheffield, United Kingdom;
3
State Key Laboratory of Electroanaytical Chemistry, Changchun Institute of Applied
Chemistry Chinese Academy of Sciences, Changchun, P. R. China
Spores, dormant cell types of Bacillus subtilis, are incased in thick proteinaceous multilayered
shell, called the coat, with significant protective role from the environment. While
providing high level of resistance, the coat allows the spore to respond to the renewed
presence of nutrients and start the cell growth in the process called germination. The
unique properties of the coat are determined by the architecture of complex spore coat
structure. Being formed by more than 70 different proteins, two main layer of coat are
easily distinguished – the lamellar inner coat and thick striated outer coat. The order of
assembly and final destination of the coat structural components rely mainly on specific
protein-protein interactions and on the action of small group of morphogenetic proteins
which guide the deposition of rest of the coat components onto the spore surface. Since
the process of assembly is still poorly understood, by searching for direct protein-protein
interactions we want to gradually generate the data to obtain the entire picture of whole
coat formation event.
In our studies we implemented yeast two hybrid system and other genetic and biochemical
methods to examine protein interactions among a group of morphogenetic coat
proteins and proteins of coat insoluble fraction. Investigation of properties of individual
recombinant coat proteins showed, that they frequently form high molecular weight
oligomeric structures in vitro. We employed AFM and EM microscopy to analyze these
structures in detail.
72 XXII. Biochemistry Congress, Martin