Streptomycetes are soil-dwelling Gram-positive bacteria and can produce clinical drugs and adapt to environmental fluctuations through diverse morphological changes. The morphological development of streptomycetes features apical growth, which is determined by a tip-organizing center containing machinery for the synthesis of a cellulose-like glycan deposited at the cell surface.
This thesis demonstrated that the cellulose-like glycan likely cellulose and the related synthesis machinery are unique in comparison with other Gram-negative cellulose synthesis systems. It showed that the synthesis of this glycan is performed by the glycosyltransferase ClsA and matured galactose-oxidase protein GlxA. Subsequently, the lytic polysaccharides monooxygenase LpmP and the glucanase ClsZ, adjacent to CslA/GlxA, cooperatively cleave peptidoglycan and create a passage to assist the exposure of this glycan on cell surface. In addition, this thesis also revealed coordination...
Show moreStreptomycetes are soil-dwelling Gram-positive bacteria and can produce clinical drugs and adapt to environmental fluctuations through diverse morphological changes. The morphological development of streptomycetes features apical growth, which is determined by a tip-organizing center containing machinery for the synthesis of a cellulose-like glycan deposited at the cell surface.
This thesis demonstrated that the cellulose-like glycan likely cellulose and the related synthesis machinery are unique in comparison with other Gram-negative cellulose synthesis systems. It showed that the synthesis of this glycan is performed by the glycosyltransferase ClsA and matured galactose-oxidase protein GlxA. Subsequently, the lytic polysaccharides monooxygenase LpmP and the glucanase ClsZ, adjacent to CslA/GlxA, cooperatively cleave peptidoglycan and create a passage to assist the exposure of this glycan on cell surface. In addition, this thesis also revealed coordination of polar growth determinants is performed by a stomatin-like protein StlP, which locates in the same gene cluster with CslA/GlxA/CslZ/LpmP. Oligomerization of StlP forms a fluid microdomain at hyphal tips, which spatially confines the whole tip organizing center. Furthermore, this thesis further showed that the cellulose-like glycan of Streptomyces coelicolor is responsible for the aggregation of clumps, which is distinct from Streptomyces lividans where this glycan mediates germlings’ aggregation.
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