INVESTIGADORES
RUSSO Daniela Marta
congresos y reuniones científicas
Título:
Extracellular components that define Rhizobium leguminosarum biofilm matrix architecture
Autor/es:
ABDIAN, P.; VOZZA, N.; CARAMELO, J.; VON BILDERLING, C.; RUSSO, D.M.; PIETRASANTA, L. ZORREGUIETA, A
Lugar:
Vienna
Reunión:
Congreso; Biofilms 6. International Conference on Microbial Biofilms; 2014
Institución organizadora:
Universidad de Austria
Resumen:
Rhizobia
are soil bacteria that interact with leguminous plants inducing nitrogen-fixing
root
nodules. They grow in varied environmental
conditions producing different types of biofilms. We study the biofilms formed
by R. leguminosarum in vitro, a process probably relevant to the attachment
of cells to soil particles. The typical architecture of a mature biofilm
consists of layers of cells attached to each other by lateral interactions,
forming clusters interlaced by water channels. The main component of the matrix
is an acidic exopolysaccharide (EPS) that provides support to the biofilm
structure. Moreover R. leguminosarum produces
a capsular polysaccharide (CPS) that seems involved in surface attachment at
the onset of biofilm formation. Proteins secreted by a type I secretion system
are also involved. Interestingly, some of them possess one or more
cadherin-like domains that confer carbohydrate binding ability. Among them, we
have characterized RapA2, a unipolar calcium binding lectin that specifically recognizes
the EPS; and the Ply glycanases that regulate the length of EPS molecules. A characteristic
distribution of EPS molecules length is important to build up an ordered polysaccharide
network. A model depicting the interaction of RapA, Ply glycanases and acidic polysaccharides
during the progress of biofilm matrix development is presented.