Genetically-tunable mechanical properties of bacterial functional amyloid nanofibers
Author
Abdelwahab, M. T.
Kalyoncu, E.
Onur, T.
Baykara, M. Z.
Seker U.O.S.
Date
2017Source Title
Langmuir
Print ISSN
0743-7463
Publisher
American Chemical Society
Volume
33
Issue
17
Pages
4337 - 4345
Language
English
Type
ArticleItem Usage Stats
118
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Abstract
Bacterial biofilms are highly ordered, complex, dynamic material systems including cells, carbohydrates, and proteins. They are known to be resistant against chemical, physical, and biological disturbances. These superior properties make them promising candidates for next generation biomaterials. Here we investigated the morphological and mechanical properties (in terms of Young’s modulus) of genetically-engineered bacterial amyloid nanofibers of Escherichia coli (E. coli) by imaging and force spectroscopy conducted via atomic force microscopy (AFM). In particular, we tuned the expression and biochemical properties of the major and minor biofilm proteins of E. coli (CsgA and CsgB, respectively). Using appropriate mutants, amyloid nanofibers constituting biofilm backbones are formed with different combinations of CsgA and CsgB, as well as the optional addition of tagging sequences. AFM imaging and force spectroscopy are used to probe the morphology and measure the Young’s moduli of biofilm protein nanofibers as a function of protein composition. The obtained results reveal that genetically-controlled secretion of biofilm protein components may lead to the rational tuning of Young’s moduli of biofilms as promising candidates at the bionano interface.
Keywords
Atomic force microscopyBiofilms
Escherichia coli
Glycoproteins
Mechanical properties
Nanofibers
Bacterial biofilm
Bio-nano interfaces
Biochemical properties
Escherichia coli (E. coli)
Force spectroscopy
Protein components
Protein composition
Protein nanofibers
Proteins