Physical Virology: Direct Measurement of Phage phi29 Stiffness Provides Evidence of Internal Pressure (Small 15/2012).
Summary of "Physical Virology: Direct Measurement of Phage phi29 Stiffness Provides Evidence of Internal Pressure (Small 15/2012)."
A 3D AFM topography rendition of a phage phi29 (red) adsorbed on mica (blue) is shown by P. J. de Pablo and coworkers, where part of the viral DNA (yellow) has been ejected through the tail. The phi29 bacteriophage translocates part of its DNA into the host by releasing the elastic energy arising from the internal pressure created during the DNA-packing process. Pushing with the AFM tip on the phage enables the direct measurement of the stiffness to estimate its internal pressure, just as a tyre may be pressed with fingers.
Affiliation
Dpto. Física de la Materia Condensada, Universidad Autónoma de Madrid, 28049-Madrid, Spain.
Journal Details
This article was published in the following journal.
Name: Small (Weinheim an der Bergstrasse, Germany)
ISSN: 1613-6829
Pages: 2365
Links
- PubMed Source: http://www.ncbi.nlm.nih.gov/pubmed/22859378
- DOI: http://dx.doi.org/10.1002/smll.201290082
Medical and Biotech [MESH] Definitions
Anaerobic Threshold
The oxygen consumption level above which aerobic energy production is supplemented by anaerobic mechanisms during exercise, resulting in a sustained increase in lactate concentration and metabolic acidosis. The anaerobic threshold is affected by factors that modify oxygen delivery to the tissues; it is low in patients with heart disease. Methods of measurement include direct measure of lactate concentration, direct measurement of bicarbonate concentration, and gas exchange measurements.
Rna Phages
Bacteriophages whose genetic material is RNA, which is single-stranded in all except the Pseudomonas phage phi 6 (BACTERIOPHAGE PHI 6). All RNA phages infect their host bacteria via the host's surface pili. Some frequently encountered RNA phages are: BF23, F2, R17, fr, PhiCb5, PhiCb12r, PhiCb8r, PhiCb23r, 7s, PP7, Q beta phage, MS2 phage, and BACTERIOPHAGE PHI 6.
Conversion Disorder
A disorder whose predominant feature is a loss or alteration in physical functioning that suggests a physical disorder but that is actually a direct expression of a psychological conflict or need.
Attachment Sites, Microbiological
Specific loci on both the bacterial DNA (attB) and the phage DNA (attP) which delineate the sites where recombination takes place between them, as the phage DNA becomes integrated (inserted) into the BACTERIAL DNA during LYSOGENY.
Lysogeny
The phenomenon by which a temperate phage incorporates itself into the DNA of a bacterial host, establishing a kind of symbiotic relation between PROPHAGE and bacterium which results in the perpetuation of the prophage in all the descendants of the bacterium. Upon induction (VIRUS ACTIVATION) by various agents, such as ultraviolet radiation, the phage is released, which then becomes virulent and lyses the bacterium.
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