What is the molecular composition of the proteins and polysaccharides that are secreted by B. subtilis cells?

We purify the proteins and polysaccharides from biofilms and determine their composition. We then study the conditions in vitro that lead to the formation of networks made of single and multiple ECM components. The networks' mechanical and structural properties are characterized using imaging techniques (Atomic force microscopy, electron microscopy) as well as spectroscopic techniques (Circular dichroism, Nuclear magnetic resonance) to determine the structural features of the ECM components before and after they assemble into networks.

Publications:

Böhning, J., Ghrayeb, M., Pedebos, C. et al. Donor-strand exchange drives assembly of the TasA scaffold in Bacillus subtilis biofilms. Nat Commun 13, 7082 (2022).

Ghrayeb, M.; Hayet, S.; Lester-Zer, N.; Levi-Kalisman, Y.; Chai, L. Fibrilar Polymorphism of the Bacterial Extracellular Matrix Protein TasA. Microorganisms 2021, 9, 529.

Azulay DN, Ghrayeb M, Ktorza IBS, Nir I, Nasser R, Harel YS, Chai L. Colloidal-like aggregation of a functional amyloid protein. Physical Chemistry Chemical Physics [Internet]. 2020;22 :23286-23294.

Abbasi R, Mousa R, Dekel N, Amartely H, Danieli T, Lebendiker M, Levi-Kalisman Y, Shalev DE, Metanis N, Chai L. The bacterial extracellular matrix protein TapA is a two‐domain partially disordered protein. CHEMBIOCHEM [Internet]. 2018. 

Malishev R, Abassi R, Jelinek R, Chai L. Bacterial model membranes reshape fibrillation of a functional amyloid protein. Biochemistry [Internet]. 2018;57 (35) :5230–5238.