84 research outputs found
Amyloid structures as biofilm matrix scaffolds
Recent insights into bacterial biofilm matrix structures have induced a paradigm shift toward the recognition of amyloid fibers
as common building block structures that confer stability to the exopolysaccharide matrix. Here we describe the functional amyloid
systems related to biofilm matrix formation in both Gram-negative and Gram-positive bacteria and recent knowledge regarding
the interaction of amyloids with other biofilm matrix components such as extracellular DNA (eDNA) and the host immune
system. In addition, we summarize the efforts to identify compounds that target amyloid fibers for therapeutic purposes
and recent developments that take advantage of the amyloid structure to engineer amyloid fibers of bacterial biofilm matrices for
biotechnological applications.This work, including the efforts of Jaione Valle, was funded by Ministerio
de Economía y Competitividad (MINECO) (AGL2011-23954). This
work, including the efforts of Íñigo Lasa, was funded by Ministerio de
Economía y Competitividad (MINECO) (BIO2011-30503-C02-02 and
BIO2014-53530-R)
Bacterial biofilm functionalization through Bap amyloid engineering
Biofilm engineering has emerged as a controllable way to fabricate living structures with programmable functionalities. The amyloidogenic proteins comprising the biofilms can be engineered to create self-assembling extracellular functionalized surfaces. In this regard, facultative amyloids, which play a dual role in biofilm formation by acting as adhesins in their native conformation and as matrix scaffolds when they polymerize into amyloid-like fibrillar structures, are interesting candidates. Here, we report the use of the facultative amyloid-like Bap protein of Staphylococcus aureus as a tool to decorate the extracellular biofilm matrix or the bacterial cell surface with a battery of functional domains or proteins. We demonstrate that the localization of the functional tags can be change by simply modulating the pH of the medium. Using Bap features, we build a tool for trapping and covalent immobilizing molecules at bacterial cell surface or at the biofilm matrix based on the SpyTag/SpyCatcher system. Finally, we show that the cell wall of several Gram-positive bacteria could be functionalized through the external addition of the recombinant engineered Bap-amyloid domain. Overall, this work shows a simple and modulable system for biofilm functionalization based on the facultative protein Bap. © 2022, The Author(s).This research was supported by grants from the Spanish Ministry of Science and Technology RTI2018-096011-B-I00 to J.V. and PID2020-113494RB-I00 to IL. L.M.-C. was supported by the predoctoral program of the Universidad Pública de Navarra
Estudio funcional y estructural de la región B de Bap y su rol en el desarrollo de biofilms en S.aureus
Trabajo presentado en la X Reunión de Microbiología Molecular, celebrada en Segovia del 9 al 11 de junio de 2014.Peer Reviewe
Near-infrared fluorescence imaging as an alternative to bioluminescent bacteria to monitor biomaterial-associated infections
Biomaterial-associated infection is one of the most common complications related with the
implantation of any biomedical device. Several in vivo imaging platforms have emerged as
powerful diagnostic tools to longitudinally monitor biomaterial-associated infections in small
animal models. In this study, we directly compared two imaging approaches: bacteria engineered
to produce luciferase to generate bioluminescence and reactive oxygen species (ROS) imaging of
the inflammatory response associated with the infected implant. We performed longitudinal
imaging of bioluminescence associated with bacteria strains expressing plasmid-integrated
luciferase driven by different promoters or a strain with the luciferase gene integrated into the
chromosome. These luminescent strains provided adequate signal for acute (0–4 days) monitoring
of the infection, but the bioluminescence signal decreased over time and leveled off by 7 days
post-implantation. This loss in bioluminescence signal was attributed to changes in the metabolic
activity of the bacteria. In contrast, near-infrared fluorescence imaging of ROS associated with
inflammation to the implant provided sensitive and dose-dependent signals of biomaterialassociated
bacteria. ROS imaging exhibited higher sensitivity than the bioluminescence imaging
and was independent of the bacteria strain. Near-infrared fluorescence imaging of inflammatory
responses represents a powerful alternative to bioluminescence imaging for monitoring
biomaterial-associated bacterial infections.This work was supported by the Ministerio of Economía y Competitividad (BIO2010-21049, 201120E092), the U.S.A. National Institutes of Health grant R21 AI094624 (A.J.G.), the Georgia Tech/Emory Center for the Engineering of Living Tissues, the Atlanta Clinical and
Translational Science Institute under PHS Grant UL RR025008 from the Clinical and Translational Science Award Program
Evaluation of Surface Microtopography Engineered by Direct Laser Interference for Bacterial Anti-Biofouling
© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Modification of the biomaterial surface topography is a promising strategy to prevent bacterial adhesion and biofilm formation. In this study, we use direct laser interference patterning (DLIP) to modify polystyrene surface topography at sub-micrometer scale. The results revealed that three-dimensional micrometer structures have a profound impact on bacterial adhesion. Thus, line- and pillar-like patterns enhanced S. aureus adhesion, whereas complex lamella microtopography reduced S. aureus adhesion in static and continuous flow culture conditions. Interestingly, lamella-like textured surfaces retained the capacity to inhibit S. aureus adhesion both when the surface is coated with human serum proteins and when the material is implanted subcutaneously in a foreign-body associated infection model.J. Valle was supported by Spanish Ministry of Science and Innovation “Ramón y Cajal” contract. This research was supported by grants AGL2011-23954 and BIO2011-30503-C02-02 from the Spanish Ministry of Economy and Competitivity and IIQ14066. RI1 from Innovation Department of the Government of Navarra. A. Lasagni, D. Langhenirich, and R. Helbig thank the Deutsche Forschungsgemeinschaft (DFG) for the financial support of the project “Mechanically stable anti-adhesive polymer surfaces” (LA-2513 4-1).Peer Reviewe
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