Bacteriophage type

Keywords Staphylococcus aureus molecnlar diagnostics species identification mobile genetics elements bacteriophages typing methods toxigenic strains... 

Pantucek R, Doskar J, Riizickova V, Kasparek P, Oracova E, Kvardova V, Rosypal S (2004) Identification of bacteriophage types and their carriage in Staphylococcus aureus. Arch Virol 149 1689-1703... 

Bacteriophage typing. The very high degree of specificity of a phage for its host cell is used to identify species and strains. Very vaiuabie in epidemioiogicai investigations. About 24 h required for resuits for most aerobic bacteria. 

HAS BACTERIOPHAGE TYPING BEEN USED IN THIS GENUS ... 

Wamecke D, Schwartz AS and Hofer M (1982) Properties of the transport system for glucose in Propionibacterium freudenreichii ssp. shermanii. Zbl Bakt Hyg, Abt IC 3 547-548 Wawszkiewicz EL and Barker HA (1968) Erythritol metabolism by Propionibacterium pentosaceum. The overall reaction sequence. J Biol Chem 243 1948-1956 Webster GF and Cummins CS (1978) Use of bacteriophage typing to distinguish Propionibacterium acnes types I and II. J Clin Microbiol 7 84-90 Wegner WS, Reeves HC, Rabin R and Ajl SJ (1968) Alternative pathways of metabolism of short chain fatty acids. Bacteriol Rev 32 1-26... 

One of the most striking results that has emerged from the high-resolution crystallographic studies of these icosahedral viruses is that their coat proteins have the same basic core structure, that of a jelly roll barrel, which was discussed in Chapter 5. This is true of plant, insect, and mammalian viruses. In the case of the picornaviruses, VPl, VP2, and VP3 all have the same jelly roll structure as the subunits of satellite tobacco necrosis virus, tomato bushy stunt virus, and the other T = 3 plant viruses. Not every spherical virus has subunit structures of the jelly roll type. As we will see, the subunits of the RNA bacteriophage, MS2, and those of alphavirus cores have quite different structures, although they do form regular icosahedral shells. 

Lysozyme from bacteriophage T4 is a 164 amino acid polypeptide chain that folds into two domains (Figure 17.3) There are no disulfide bridges the two cysteine residues in the amino acid sequence, Cys 54 and Cys 97, are far apart in the folded structure. The stability of both the wild-type and mutant proteins is expressed as the melting temperature, Tm, which is the temperature at which 50% of the enzyme is inactivated during reversible beat denat-uration. For the wild-type T4 lysozyme the Tm is 41.9 °C. 

An alternative to repeated cloning of PCR products is a recombination-based approach developed by Liu et al. (1998) to permit the cloning of a PCR product into a plasmid and the rapid conversion of the plasmid to a number of different expression systems without the necessity of cloning the PCR product multiple, independent times. The method, termed the univector plasmid-fusion system (UPS), involves the insertion of the PCR product into a particular type of plasmid, called the univector, which can then be placed under the control of a variety of promoters or fused in-frame to various tag sequences. The system is based upon plasmid fusion using the Cre-lox site-specific recombination system of bacteriophage PI (Sternberg et al., 1981). The Cre enzyme is a site-specific recombinase that catalyzes recombination between two 34 base pair (bp) loxP sequences and is involved in the resolution of dimers formed during replication of the... 

Classification of bacterial viruses In the bacterial viruses, a formal classification scheme is rarely used. Rather, each bacterial virus is designated in terms of its principal bacterial host, followed by an arbitrary alphanumeric. Thus, we speak of T4 virus of Escherichia coli or P22 virus of Salmonella typhimurium. An overview of some of the major types of bacterial viruses is given later. We should note, however, that although a bacterial virus may be designated in reference to its principal host, the actual host range of the virus may be broader. Thus, bacteriophage Mu, generally studied with Escherichia coli, also infects Citrobacter and Salmonella. 

DNA very efficiently into their host bacteria. A single bacteriophage DNA can be replicated approximately 100-fold or more per cell depending on the type of phage and its host. 

An essential feature of the cloning vector used is that it must be capable of self-replication in the cell into which it is introduced, which is usually E. coli. Two of the most commonly used types of vector in conjunction with E. coli are plasmids and bacteriophage X. Plasmids are circular extra-chromosomal DNA molecules, generally between 5000 and 350 0000 bp in length, that are found naturally in a wide range of bacteria. They generally house several... 

More recently, triple /1-spiral repeats have been identified in mammalian reovirus type 3 fiber (Chappell et al., 2002 Fig. 4A), avian reovirus fiber (Guardado Calvo et al., 2005 Fig. 4B), and bacteriophage PRD1 P5 protein (Merckel et al., 2005 Fig. 4C). In the latter two cases, it appears that only two repeats are present, just N-terminal to the head domain. Mammalian reovirus fiber contains eight putative triple /1-spiral repeats, of which three were resolved in the crystal structure (Chappell et al., 2002). 

Yang, X., Lee,J., Mahony, E. M., Kwong, P. D., Wyatt, R., and Sodroski.J. (2002). Highly stable trimers formed by human immunodeficiency virus type 1 envelope glycoproteins fused with the trimeric motif of T4 bacteriophage fibritin. J. Virol. 76, 4634-4642. 

---