Fd virus

More than half a century ago, Bawden and Pirie [77] found that aqueous solutions of tobacco mosaic virus (TMV), a charged rodlike virus, formed a liquid crystal phase at as very low a concentration as 2%. To explain such remarkable liquid crystallinity was one of the central themes in the famous 1949 paper of Onsager [2], However, systematic experimental studies on the phase behavior in stiff polyelectrolyte solutions have begun only recently. At present, phase equilibrium data on aqueous solutions qualified for quantitative discussion are available for four stiff polyelectrolytes, TMV, DNA, xanthan (a double helical polysaccharide), and fd-virus. 

Figure 11 shows the phase boundary concentration data for aqueous Na salt xanthan [78], fd-virus [24], and TMV [23] with added salt. In all these systems, Ci and cA are very low at low added salt concentration Cs or ionic strength I, and increase with Cs or I. Since such low phase boundary concentrations are not usually observed for neutral liquid-crystalline polymer solutions, it is apparent that polyion electrostatic interactions play an important role in the phase equilibria of these systems. 

Fig. lla-c. Phase boundary mass concentrations for aqueous solutions of three stiff polyions a xanthan (a double-helical polysaccharide) [78] b fd-virus [24] c tobacco mosaic virus (TMV) [23], Circles, experimental results curves, predictions by the first-order perturbation theory (see text)... 

Fig. 6.14 Micrograph of fd-virus particles, reproduced from [27] with permission from the authors...

Fig. 6.15 Phase diagrams of dextran/fd-virus mixtures. Data points are measured coexistences. Phase diagram was measured at ionic strength of 100 mM at pH = 8.15 with added 500kDa dextrans. Redrawn from [31]...

The Tobacco Mosaic Virus (TMV) and fd viruses were the first model systems for rod-like structures investigated by SLS and SANS [110-113], Whereas... 

Fig. 7. Product q u,L (L the rod length) as a function of the reduced polyion concentration Cp/c with c the overlap concentration for different rod-like polyions ( fd-virus TMV series 1 cf 10 m, series 2 c 4.7 x 10" m, series 3 cf 1.7 x 10" m). The solid lines represent the scaling behavior with the exponents 1/3 and 1/2, respectively (taken from [113])...

Nematic states occur also in nonionic monomeric and polymeric surfactant solutions, living amoeboid cells i and rigid or semiflexible polymeric rods, such as fd virus in water solutions. - We note that colloidal suspension of semiflexible virus particles also form nematic phases. - ... 

Schmidt, et al. studied the rheological properties of solutions of fd-virus, using classical mechanical and magnetic tweezers rheometry to determine G and G" (101). Macroscopic and microscopic measurements were in reasonable agreement. The observed frequency dependence of G at low frequency was much weaker than predicted by some modem theoretical calculations(102). Comparison was made with actin solutions to separate fundamental properties from single-system peculiarities. Actin aggregation is extremely sensitive to a wide variety of factors. 

Schmidt, et al. conclude that alternative physical systems, such as fd-virus solutions, are far superior to F-actin solutions as models for testing theories of polymer dynamics. 

Figure 2.26 Cross sections of the Fourier transforms of the confocal images parallel and perpendicular to the director for a fd virus concentration of ( ) = 0.52 (a), and the parallel and perpendicular cross sections of the scattering intensity as found from SALS (b).

Figure 5.12 Schematic representations of the main types of bacterial viruses. Those discussed in detail are fd, M13,

Bushman FD, Engelman A, Palmer I, Wingfield P, Craigie R. Domains of the integrase protein of human immunodeficiency virus type 1 responsible for polynucleotidyl transfer and zinc binding. Proc Natl Acad Sci USA 1993 90 3428-3432. 

Bushman FD, Wang B. Rous sarcoma virus integrase protein Mapping functions for catalysis and substrate binding. J Virol 1994 68 2215-2223. 

Figure 7-7 Structure of the virus fd protein sheath. (A) Left. A single coat subunit, with its N terminus towards the top, as if moved from the left side of the sheath. The dark circles represent charged atoms of Asp, Glu, and Lys side chains. The backbone of the protein is a C diagram. The positively charged atoms near the C terminus line the inner surface of the sheath neutralizing the negative charge of the DNA core. Right.

Virus fd protein sheath 335s Virus 4>X174... 

FD-483 observation 1 SOPX, GMP Computer Systems. The procedure describes establishing a written security policy, maintain an access control roster, and virus protection will be installed. There is no written security policy, however, and there is no virus protection installed for theYsystem. 

The E. coli filamentous bacteriophages, such as M13, fd, and fl, are the most commonly used viruses in biological display systems. Their genomes are small... 

Banner DW, Nave C, Marvin DA, Structure of the protein and DNA in fd filamentous bacterial virus, Nature, 289 814-816, 1981. 

Roy MJ, Wu MS, Barr LJ, Fuller JT, Tussey LG, Speller S, Culp J, Burkholder JK, Swain WF, Dixon RM, Widera G, Vessey R, King A, Ogg G, Gallimore A, Haynes JR, Heydenburg FD. Induction of antigen-specific CD8+ T cells, T helper cells, and protective levels of antibody in humans by particle-mediated administration of a hepatitis B virus DNA vaccine. Vaccine 2000 19 764-78. 

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