[Todos] coloquio extraordinario hoy, cambio de aula

[pdmitruk en df.uba.ar]

El coloquio de Harry Swinney hoy miercoles 17/3, 16hs, se realizara'
en el Aula E24, entrepiso, Pab. I.


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Deadly competition between bacterial colonies

A few bacteria on a surface (e.g., skin or a medical instrument) can
multiply rapidly and grow into a colony consisting of more than 10^9
bacteria and spanning several centimeters. What happens when
neighboring colonies of bacteria grow and approach one another? Our
research on a species of bacteria found in soil 'Paenibacillus
dendritiformis' reveals that these bacteria mutually inhibit growth
through secretions that become lethal if the concentration exceeds a
well-defined threshold. Analysis of the secretions reveals the
presence of subtilisin (a protein that promotes growth) and a
previously unknown toxin, Slf (sibling lethal factor). An immediate
question is why doesn't the toxin kill the bacteria secreting it? Our
group has developed a mathematical model that helps answer this
question. It is found that The gene that encodes Slf is homologous to
genes known to occur in many other bacteria; thus the mechanism
observed for self-regulation of growth of colonies of P.
dendritiformis may well occur in other bacteria.

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