实验基础

DC-SIGN and L-SIGN are C-type lectins that recognize carbohydrate structures present on viral glycoproteins and function as attachment factors for several enveloped viruses. DC-SIGN and L-SIGN enhance viral entry and facilitate infection of cells that express the cognate entry rec ...

Methods for generating recombinant vaccinia viruses for the expression of foreign viral glycoproteins in mammalian cell lines and the purification of expressed viral glycoproteins are described. These methods are based on many years of experience with the influenza hemaggluti ...

The respiratory syncytial virus (RSV) fusion (F) protein is synthesized as an inactive precursor (F0), which subsequently undergoes post-translational cleavage to give the disulphide bond-linked F1 and F2 subunits. The methodology detailing the use of two-dimensional electrop ...

The influence of viral envelope glycans is often overlooked, but one should bear in mind that variable glycosylation may affect the properties of viral envelope glycoproteins and potentially alter the course of an infection. Hence, there is a need for simple methods that can be use to identify ch ...

The spike (S) glycoprotein of coronaviruses is known to be essential in the binding of the virus to the host cell at the advent of the infection process. To study the maturation pathway of the S glycoprotein of the severe acute respiratory syndrome (SARS)-coronavirus (CoV) within the host cell, a T7/va ...

Viruses are omnipresent and extraordinarily abundant in the microbial ecosystems of water, soil, and sediment. In nearly every reported case for aquatic and porous media environments (soils and sediments) viral abundance exceeds that of co-occurring host populations by 10–100-fo ...

Most bacterial cells carry prophage genomes either integrated into the host DNA or present as repressed plasmids. Methods are described for the induction of prophages using Mitomycin C, and for the isolation of prophage-cured bacterial cell lines.

Classical bacterial enrichment devised by Sergius Winogradsky (1856–1953) and Martinus Beijerinck (1851–1931) can be modified to enrich for bacteria-specific viruses. In this chapter simple protocols are presented for the enrichment of phages from water samples, such as sewage, a ...

The detection and isolation of viruses directly from high temperature (80C) acidic (pH

Cyanophages are a group of viruses which specifically infect cyanobacteria. The cyanobacteria are predominantly aquatic phototrophic bacteria and the two dominant genera Synechococcus and Prochlorococcus contribute significantly to primary production in the oceans. C ...

Viruses are detected via either biological properties such as plaque formation or physical properties. The physical properties include appearance during microscopy and DNA sequence derived from community sequencing. The assumption is that these procedures will succeed for mo ...

Determination of virus abundance using epifluorescence microscopy is a rapid and accurate method. The protocol requires the concentration of virus particles by collection on a filter. The nucleic acid in the virus particles is then stained with a fluorescent stain and the sample viewed wi ...

Rapid identification and enumeration of the numerically important bacteriophages has been till recently a major limitation for studies of virus ecology. The development of sensitive nucleic acid stains, in combination with flow cytometric techniques, has changed this. The flow cy ...

Prokaryote viruses include 14 officially accepted families and at least five other potential families awaiting classification. Approximately 5,500 prokaryote viruses have been examined in the electron microscope. Classification has a predictive value and is invaluable to c ...

Negative staining of purified viruses is the most important electron microscopical technique in virology. The principal stains are phosphotungstate and uranyl acetate, both of which have problems and advantages. Particular problems are encountered in photography, calibrat ...

The host range of a bacteriophage is defined by what bacterial genera, species and strains it can lyse; it is one of the defining biological characteristics of a particular bacterial virus. Because of host factors such as masking by O antigens that affects injection and the presence of restriction ...

Laboratory characterization of bacteriophage growth traditionally is done either in broth cultures or in semisolid agar media. These two environments may be distinguished in terms of their spatial structure, i.e., the degree to which they limit diffusion, motility, and environment ...

Practical methods are described for studying the adsorption rate of bacteriophages to cells and the interaction between these viruses and their surface receptors.

Bacteriophage growth may be differentiated into sequential steps: (i) phage collision with an adsorption-susceptible bacterium, (ii) virion attachment, (iii) virion nucleic acid uptake, (iv) an eclipse period during which infections synthesize phage proteins and nucleic acid, ...

In microbiology, preservation of an archival stock or a “master stock” of a given microorganism is essential for many reasons including scientific research, conservation of the genetic resources and providing the foundation for several biotechnological processes. The objective ...