Biomaterial Database

Biogenesis of Lysobacter sp. XL1 vesicles. 2015

Irina V Kudryakova, and Natalia E Suzina, and Natalia V Vasilyeva

Laboratory of Microbial Cell Surface Biochemistry, G.K. Skryabin Institute of Biochemistry and Physiology of Microorganisms, Russian Academy of Sciences, 5 Pr. Nauki, Pushchino, Moscow Region, 142290 Russia kudryakovairina@yandex.ru.

The Gram-negative bacterium Lysobacter sp. XL1 forms vesicles and, using them, secretes an extracellular protein, bacteriolytic endopeptidase L5. Fractionation of a Lysobacter sp. XL1 vesicle preparation in a sucrose density gradient yielded four vesicle fractions of 30%, 35%, 40% and 45% sucrose. The size of most vesicles concentrated in 30% and 35% sucrose fractions were 40-65 and 65-100 nm, respectively. Electrophoresis and immunoblotting showed vesicles of the 30% fraction differed from those in the other fractions not only in density but also in protein content. Protein L5 was found to be secreted into the extracellular medium only by means of vesicles of the 30% sucrose fraction. Electron microscopic immunocytochemistry of Lysobacter sp. XL1 cells showed protein L5 to be distributed unevenly along the periplasmic space and to be concentrated in certain periplasmic loci adjacent to the outer membrane. It was in those loci where vesiculation occurred. A model of the formation of Lysobacter sp. XL1 vesicles is proposed based on the data obtained.

UI	MeSH Term	Description	Entries
D008854	Microscopy, Electron	Microscopy using an electron beam, instead of light, to visualize the sample, thereby allowing much greater magnification. The interactions of ELECTRONS with specimens are used to provide information about the fine structure of that specimen. In TRANSMISSION ELECTRON MICROSCOPY the reactions of the electrons that are transmitted through the specimen are imaged. In SCANNING ELECTRON MICROSCOPY an electron beam falls at a non-normal angle on the specimen and the image is derived from the reactions occurring above the plane of the specimen.	Electron Microscopy
D010450	Endopeptidases	A subclass of PEPTIDE HYDROLASES that catalyze the internal cleavage of PEPTIDES or PROTEINS.	Endopeptidase,Peptide Peptidohydrolases
D002499	Centrifugation, Density Gradient	Separation of particles according to density by employing a gradient of varying densities. At equilibrium each particle settles in the gradient at a point equal to its density. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)	Centrifugations, Density Gradient,Density Gradient Centrifugation,Density Gradient Centrifugations,Gradient Centrifugation, Density,Gradient Centrifugations, Density
D001433	Bacteriolysis	Rupture of bacterial cells due to mechanical force, chemical action, or the lytic growth of BACTERIOPHAGES.	Bacteriolyses
D053528	Lysobacter	A genus of gram-negative, rod-shaped, gliding bacteria in the family XANTHOMONADACEAE. Strongly proteolytic, it is involved in lysing a variety of microorganisms.
D021961	Cell Membrane Structures	Structures which are part of the CELL MEMBRANE or have cell membrane as a major part of their structure.	Cell Membrane Structure,Membrane Structure, Cell,Membrane Structures, Cell,Structure, Cell Membrane,Structures, Cell Membrane