Caltech Library System

About | Browse | Search | Caltech Student Instructions

Type of Document	Dissertation
Author	Sato, Gordon
URN	etd-04292005-085816
Persistent URL	http://resolver.caltech.edu/CaltechETD:etd-04292005-085816
Title	The effect of urea on cofactor requiring bacteriophage
Degree	PhD
Option	Biology
Advisory Committee	Advisor Name Title Max Delbruck Committee Chair
Keywords	none
Date of Defense	1956-01-01
Availability	unrestricted
Abstract Some strains of bacteriophage must be activated by cofactor before they can adsorb to their bacterial hosts. Up to the present time, the only compounds shown to possess cofactor activity have been certain amino acids and amino acid analogues. In the present study, it is shown that urea, a well known denaturing agent, is capable of activating cofactor requiring phage. By a process, statistically independent of the activation process, urea also kills the phage. Experiments are performed to characterize the properties of urea-activated phage, in regard to stability of urea induced adsorbability and in regard to adsorption rate. The kinetics of the urea activation process and of the urea killing process are studied in detail. Both processes are shown to depend on concentration of urea, temperature, and pH in a manner similar to denaturation of protein by urea. It is concluded that urea effects the activation of phage by denaturing the protein of the phage adsorption organ. It is further postulated that the action of cofactors consists in a denaturation of phage protein. The biological implications of this hypothesis are discussed.
Files	Filename       Size       Approximate Download Time (Hours:Minutes:Seconds)     28.8 Modem   56K Modem   ISDN (64 Kb)   ISDN (128 Kb)   Higher-speed Access    Sato_gh_1956.pdf 5.74 Mb 00:26:33 00:13:39 00:11:56 00:05:58 00:00:30