title: In vivo crystal formation in Escherichia coli of an over-expressed soluble form of penicillin-binding protein 5.
abstract: Accumulation of either native membrane-bound or soluble variants of PBP5 over-expressed in the cytoplasm was investigated by electron microscopy of ultra-thin sections. One of the soluble forms of PBP5 (PBP5s353) formed well-ordered crystals inside the cells. Cells sectioned perpendicular to their long axis showed a diamond-shaped crystal whereas cells cut parallel to their long axis contained a long, narrow crystal. In both sectioning directions an ordered ultrastructure was visible as shown by optical diffraction. Computer processing was used to enhance the crystal images. From this the unit cell parameters were calculated as a = 7.6 nm, b = 4 nm, c = 4.2 nm, gamma = 75 degrees. The calculated unit-cell volume of 120 nm3 is large enough to contain one protein molecule.
authors: BIOSON Research Institute, Department of Biochemistry, University of Groningen, Netherlands.
authors: M P
authors: MP
authors: van der Linden
authors: J
authors: J
authors: Vonck
authors: K A
authors: KA
authors: Sjollema
authors: W
authors: W
authors: Keck
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins; D002352:Carrier Proteins / Q000096:biosynthesis / Q000235:genetics / Q000648:ultrastructure*; D003460:Crystallization; D003593:Cytoplasm / Q000378:metabolism / Q000648:ultrastructure; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism* / Q000648:ultrastructure*; D015870:Gene Expression; D006602:Hexosyltransferases; D008854:Microscopy, Electron; D008969:Molecular Sequence Data; D002267:Muramoylpentapeptide Carboxypeptidase / Q000096:biosynthesis / Q000235:genetics / Q000648:ultrastructure*; D046915:Penicillin-Binding Proteins; D010406:Penicillins / Q000378:metabolism; D010458:Peptidyl Transferases; D012995:Solubility
chemical_list: D001426:Bacterial Proteins; D002352:Carrier Proteins; D046915:Penicillin-Binding Proteins; D010406:Penicillins; D010458:Peptidyl Transferases; D006602:Hexosyltransferases; D002267:Muramoylpentapeptide Carboxypeptidase