INVESTIGADORES
HOLLMANN Axel
congresos y reuniones científicas
Título:
Liposomes stabilized with s-layer proteins from lactobacilli
Autor/es:
HOLLMANN, AXEL; DELFEDERICO, L; DE ANTONI, GRACIELA; SEMORILE, LILIANA; DISALVO, ANIBAL
Lugar:
ROSARIO, ARGENTINA
Reunión:
Congreso; XXXV Reuninón Anual de la Sociedad Argentina de Biofísica; 2006
Resumen:
One of the commonly observed outer
surface components of cell envelopes of prokaryotic organisms, archaea and
bacteria, are crystalline arrays of proteinaceous subunits, known as surface
layers. S-layers are composed of single protein or glycoprotein species and
represent the simplest biological membrane developed during evolution Isolated S-layer subunits of numerous
organisms are able to assemble in vitro,
either in suspension, at liquid surface interfaces, on lipid films including
liposomes and on solid supports [1].
Liposome stability towards different stress factors has
been significantly enhanced when they were coated with S-layer proteins from Geobacillus stearothermophilus [2, 3]. However, the possibility to
prepare lipid particles using S-layers proteins from microorganisms with
beneficial effects for human health, as lactobacilli members, has not been
reported yet.
The stability of liposomes coated with S-layer
proteins from Lactobacillus brevis
and Lactobacillus kefir was analysed
in this study, as a previous stage to the development of a vaccine vehicle for
oral administration.
The interactions of the different S-layer proteins
with positively charged liposomes prepared with soybean lecithin or
dipalmitoylphosphatidylcholine were studied by means of the variation of the Z
potential at different protein-lipid ratios,
showing that both proteins were able to attach in a greater extent to the
surface of soybean lecithin liposomes. The capacity of these particles to
retain carboxyfluorescein or calcein by exposure to bile salts, pancreatic extract,
pH change and after a thermal shock showed that both S-layer proteins increased
the stability of the liposomes in the same magnitude. The ability of S-layer
proteins to avoid liposome fusion was studied using rhodamine in the membrane.
It was observed that fusion of liposomes coated with S-layer proteins was lower
than in the control without the protein.
The development of drug targeting and
delivery systems based on liposomes coated with functional S-layer isolated
from beneficial bacteria such as lactobacilli, appears in the light of the
present results as a possibility to enhance their efficiency and stability