Publications

cloning and expression of the filamentous bacteriophage pf1 major coat protein gene in escherichia coli. membrane protein processing and virus assembly.	a restriction fragment carrying the major coat protein gene (gene viii) was excised from the replicative form (rf) dna of the class ii filamentous bacteriophage pf1, which infects pseudomonas aeruginosa. this fragment was cloned into the expression plasmid pkk223-3, where it came under the control of the tac promoter. in transformed escherichia coli jm101 cells, in the presence of the inducer isopropyl-beta-d-thiogalactoside, the bacteriophage pf1 gene was strongly expressed. the bacteriophage p ...	1987	3309343
structural responsiveness of filamentous bacteriophage pf1: comparison of virion structure in fibers and solution. the effect of temperature and ionic strength.	x-ray diffraction from fibers and magnetically oriented solutions has been used to study the effect of changes in environment on the helical symmetry and radial structure of the pf1 virus particle. detailed analysis of equatorial scattering to a spacing of 8-10 a was used to identify small radial motions of structural elements in the virus particle. r-factor ratios were used to determine the statistical significance of observed changes. comparison of the structure of virus particles in fibers wi ...	1987	3663828
secondary structure of filamentous bacteriophage coat protein is preserved in lipid environments.	1h nuclear magnetic resonance experiments have shown that the amide hydrogens of residues 30 to 40 of bacteriophage pf1 coat protein in micelles undergo very slow exchange with solvent deuterons. the amide 1h resonances from these residues were used to monitor the structural stability of the membrane-spanning helix of the coat protein during the transition of the coat protein from its structural form, in the virus particle, to the membrane-bound form, in micelles. the helix was found to remain f ...	1988	3411609
dual importance of positive charge in the c-terminal region of filamentous bacteriophage coat protein for membrane insertion and dna-protein interaction in virus assembly.	gene viii encoding the procoat protein of the class ii filamentous bacteriophage pf1 (infecting pseudomonas aeruginosa) has been cloned and expressed in escherichia coli and subjected to site-directed mutagenesis. the two positively charged residues clustered near the c-terminus, arginine-44 and lysine-45, were systematically converted to uncharged residues and serine-41 was converted to an arginine residue. removal of positive charge in the c-terminal region of the molecule seriously impaired t ...	1989	2503933
nmr studies of the structure and dynamics of membrane-bound bacteriophage pf1 coat protein.	filamentous bacteriophage coat protein undergoes a remarkable structural transition during the viral assembly process as it is transferred from the membrane environment of the cell, where it spans the phospholipid bilayer, to the newly extruded virus particles. nuclear magnetic resonance (nmr) studies show the membrane-bound form of the 46-residue pf1 coat protein to be surprisingly complex with five distinct regions. the secondary structure consists of a long hydrophobic helix (residues 19 to 4 ...	1991	1925542
membrane-mediated assembly of filamentous bacteriophage pf1 coat protein.	filamentous bacteriophage pf1 assembles by a membrane-mediated process during which the viral dna is secreted through the membrane while being encapsulated by the major coat protein. neutron diffraction studies showed that in the virus most of the coat protein consists of two alpha-helical segments arranged end-to-end with an intervening mobile surface loop. nuclear magnetic resonance studies of the coat protein in the membrane-bound form have shown that the secondary structure is essentially id ...	1991	1925543
structural polymorphism correlated to surface charge in filamentous bacteriophages.	fiber diffraction studies are used to demonstrate that changes in the helical symmetry of the protein coat of filamentous bacterial viruses fd and m13 are correlated with changes in the surface charge. comparison of the structure of m13 and fd at ph 2 and 8 indicate that surface charge affects both the helical symmetry and flexibility of the virions. the changes in helical symmetry are similar in magnitude to that observed in the pseudomanas phage pf1 and probably reflect an inocuous side effect ...	1992	1504244
structural constraints on the display of foreign peptides on filamentous bacteriophages.	strategies for the construction of vehicles for phage display are evaluated here on the basis of structural studies of filamentous bacteriophages. potential sites for the insertion of foreign peptides into the major coat protein, gp8, of m13 are identified. currently, the insertion of peptides into gp8 has two basic limitations: all insertion sites that have been used successfully are located within 5 amino acids (aa) of the n terminus, and in virions containing only mutant coat proteins, insert ...	1993	8508959
pf1 virus structure: helical coat protein and dna with paraxial phosphates.	the helical path of the dna in filamentous bacteriophage pf1 was deduced from different kinds of existing structural information, including results from x-ray fiber diffraction. the dna has the same pitch, 16 angstroms, as the surrounding helix of protein subunits; the rise and rotation per nucleotides are 6.1 angstroms and 132 degrees, respectively; and the phosphates are 2.5 angstroms from the axis. the dna in pf1 is, therefore, the most extended and twisted dna structure known. on the basis o ...	1994	8036516
structure and organization of bacteriophage pf3 probed by raman and ultraviolet resonance raman spectroscopy.	the pseudomonas bacteriophage pf3 is a long and narrow filament consisting of a covalently closed dna single strand of 5833 bases sheathed by approximately 2500 copies of a 44-residue subunit. ultraviolet resonance raman spectra excited at 257, 244, 238, and 229 nm and off-resonance raman spectra excited at 514.5 nm are reported for pf3 in both h2o and d2o solutions. the key raman bands are assigned to specific protein and dna groups of the native virion assembly. the results are compared with p ...	2001	11148039
protein and dna residue orientations in the filamentous virus pf1 determined by polarized raman and polarized ftir spectroscopy.	the pseudomonas bacteriophage pf1 is a long ( approximately 2000 nm) and thin ( approximately 6.5 nm) filament consisting of a covalently closed, single-stranded dna genome of 7349 nucleotides coated by 7350 copies of a 46-residue alpha-helical subunit. the coat subunits are arranged as a superhelix of c(1)()s(5.4)() symmetry (class ii). polarized raman and polarized ftir spectroscopy of oriented pf1 fibers show that the packaged single-stranded dna genome is ordered specifically with respect to ...	2003	12549913
conformational dynamics of an intact virus: order parameters for the coat protein of pf1 bacteriophage.	this study has examined the atomic-level dynamics of the protein in the capsid of filamentous phage pf1. this capsid consists of approximately 7,300 small subunits of only 46 aa in a helical array around a highly extended, circular single-stranded dna molecule of 7,349 nt. measurements were made of site-specific, solid-state nmr order parameters, s, the values which are dimensionless quantities between 0 (mobile) and 1 (static) that characterize the amplitudes of molecular bond angular motions t ...	2008	18653759
bactericidal activities of cathelicidin ll-37 and select cationic lipids against the hypervirulent pseudomonas aeruginosa strain lesb58.	pseudomonas aeruginosa liverpool epidemic strain (les) infections in cystic fibrosis (cf) patients are associated with transmissibility and increased patient morbidity. this study was designed to assess the in vitro activities of cathelicidin ll-37 peptide (ll-37) and select cationic lipids against pseudomonas aeruginosa lesb58 in cf sputum and in a setting mimicking the cf airway. we found that ll-37 naturally present in airway surface fluid and some nonpeptide cationic lipid molecules such as ...	2015	25870055