title: Macroscopic amyloid fiber formation by staphylococcal biofilm associated SuhB protein.
abstract: Staphylococcus aureus is a commensal and opportunistic pathogen that causes lethal infections. Biofilm forming ability of S. aureus enhances its virulence since biofilm provides the bacteria protective shield against antibiotics and host immunity. Polysaccharide independent biofilm formation by several virulent S. aureus strains have been identified recently, where protein components substitute polysaccharide intercellular adhesin (PIA) involved in bacterial cell attachment. The suhB gene has been reported to be essential in staphylococcal PIA-independent biofilm formation. Overexpression of staphylococcal SuhB (SasuhB) in E. coli produces extracellular macroscopic fibers made of recombinant SaSuhB protein. The amyloidic nature of the fiber is evaluated by high resolution electron microscopy, X-ray fiber diffraction and amyloid specific dyes, such as Congo red and thioflavin-T binding assay. The fibers appear to be sticky in nature and bind a large number of bacterial cells. The results suggest the possible role of SaSuhB-fibers as a structural component as well as an adhesin in biofilm matrix.
authors: Department of Biotechnology, Indian Institute of Technology Kharagpur, Kharagpur 721302, West Bengal, India.
authors: Anirudha
authors: A
authors: Dutta
authors: Department of Biotechnology, Indian Institute of Technology Kharagpur, Kharagpur 721302, West Bengal, India.
authors: Sudipta
authors: S
authors: Bhattacharyya
authors: Department of Biotechnology, Indian Institute of Technology Kharagpur, Kharagpur 721302, West Bengal, India.
authors: Anirban
authors: A
authors: Kundu
authors: Department of Biotechnology, Indian Institute of Technology Kharagpur, Kharagpur 721302, West Bengal, India.
authors: Debabrata
authors: D
authors: Dutta
authors: Department of Biotechnology, Indian Institute of Technology Kharagpur, Kharagpur 721302, West Bengal, India. Electronic address: amitk@hijli.iitkgp.ernet.in.
authors: Amit Kumar
authors: AK
authors: Das
mesh_terms: D000682:Amyloid / Q000096:biosynthesis* / Q000737:chemistry; D018441:Biofilms; D010744:Phosphoric Monoester Hydrolases / Q000378:metabolism*; D011135:Polysaccharides, Bacterial / Q000378:metabolism; D013211:Staphylococcus aureus / Q000737:chemistry* / Q000201:enzymology / Q000378:metabolism
chemical_list: D000682:Amyloid; D011135:Polysaccharides, Bacterial; C113579:polysaccharide intercellular adhesin; D010744:Phosphoric Monoester Hydrolases
keywords: Amyloid fiber; Macroscopic fiber; Polysaccharide independent biofilm; SuhB