Microbial nanoscopy: A closer look at microbial cell surfaces

Institute of Condensed Matter and Nanosciences, Université Catholique de Louvain, Croix du Sud 2/18, B-1348 Louvain-la-Neuve, Belgium.
Trends in Microbiology (Impact Factor: 9.81). 09/2010; 18(9):397-405. DOI: 10.1016/j.tim.2010.06.004
Source: PubMed

ABSTRACT How cell envelope constituents are spatially organised and how they interact with the environment are key questions in microbiology. Unlike other bioimaging tools, atomic force microscopy (AFM) provides information about the nanoscale surface architecture of living cells and about the localization and interactions of their individual constituents. These past years have witnessed remarkable advances in our use of the AFM molecular toolbox to observe and force probe microbial cells. Recent milestones include the real-time imaging of the nanoscale organization of cell walls, the quantification of subcellular chemical heterogeneities, the mapping and functional analysis of individual cell wall constituents and the analysis of the mechanical properties of single receptors and sensors.

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Available from: Vincent Dupres, Jul 29, 2015
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    • "The development of a simple, fast and versatile platform to monitor in situ bacterial sporulation from a morphological and mechanical perspective at the nanoscale can provide key insights into this process. Atomic force microscopy (AFM) has rapidly emerged as an important, widely used tool in microbiology (Dufrene, 2008; Dupres et al., 2010; Muller & Dufrene, 2011). The unique advantage of the AFM is the ability not only to characterize cellular surfaces with nanoscale resolution and three dimensional imaging (Plomp et al., 2007), but also measure their nanomechanical forces (Dufrene & Pelling, 2013). "
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    Journal of Microscopy 01/2015; DOI:10.1111/jmi.12214 · 2.15 Impact Factor
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    • "In this context atomic force microscopy (AFM) has been successfully used as analytical technique able to determine the hydrophobic/hydrophilic character of the biofilm at the nanoscale [18] [19] [20] and the tremendous advances made recently in scanning probe microscopy techniques and equipment makes it a powerful tool to study the surface characteristics of biofilm [21]. AFM is based on the detection of atomic interaction forces between a sharp tip and the sample. "
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    Applied Surface Science 04/2013; 279. DOI:10.1016/j.apsusc.2013.04.128 · 2.54 Impact Factor
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    • "Hydrophobins stabilize the adhesion of spores to both natural and artificial hydrophobic surfaces , possibly generating morphogenetic signals (Scholtmeijer et al., 2001; Wosten, 2001; Linder et al., 2005b). Hydrophobins, a family of small-secreted proteins with a characteristic pattern of eight cysteine residues, have been reported in A. fumigatus to be responsible for the strong adhesion forces of 2858 ± 1010 pN during spore adhesion to surfaces (Dague et al., 2008; Dupres et al., 2010). It seems that conidium contact/attachment is required to trigger germination (Shaw et al., 2006). "
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    ABSTRACT: The biofilm phenotype is an increasingly important concept in mycological research. Recently, there has been a developing interest in whether Aspergillus species are truly able to form biofilms or not. Industrial mycologists have long been aware of biofilms and their benefit in fermentation processes, whereas clinically their role is uncertain. This review provides an update on the impact that Aspergillus biofilms have medically and industrially, and will discuss biofilm development, and our current understanding of its molecular basis. The role of exopolymeric substance and how this substance relates to antimicrobial recalcitrance will also be discussed.
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