| Three representative living system of bacteriophage-host were studied using calonmetric technique They were T4E. λE and M13E. The thermokinetial characteristics of the biological process, such as the infection and development of bacteriophages, the metabolism and growth of host cells, were parsed with the theory of thermokinetics. and the thermochemical relationship was discussed between bacteriophage and its host. Based on these work, the effects on T4E and λE living system of a bacterial and a fungal melanin, which is a scavenger of free radical, were detected with microcalorimetric method. And a mel gene from Ps. maltophilia was cloned to M13 phage, to observe the effect of foreign gene on the infection and development of Ml 3 phage.According to the thermal power-time curves of T4E system in complete medium, the thermokinetics equations, inhibitive thermokinetics equations and lytic kinetics equations were got by linear fitting. The apparent growth rate constant ki of T4E system calculated from inhibitive thermokinetics equations is bigger than the growth rate constant k of normal cells, indicating that the metabolic activity of infected cells is more intensive than that of normal cells. The phenomenon of lysis inhibition (LIN) was first detected with the microcalorimetric method.According to the thermal power-time curves of T4E system in resting medium MM, the heat output power and the amount of heat of single cell could be calculated. The heat output power of single cell (SCP) in T4E system is higher than normal cell. Heat output power of single infected cell (ISCP) exceeds that of non-infected cell by 1.23 pW to 2.03pW at various cell concentration. The metabolic activity of infected cell is enhanced by 44.57% to 61.70% in comparison to non-infected cell. It is confirmed that T4 phage infection can enhance metabolism of host cells. The phenomenon of lysis from without (LF) can be observed on the thermal power-time curve at high MOI in resting medium.The interaction between T4 phage and host cells was determined by titration calorimetric method, and the early information of T4 phage infection and penetration were got. The heat emits at once when T4 phages were mixed with cells, and the process of heat produce is similar to the enzyme-catalyzed reactions. The amount of heat includes the absorption heat and shock heat caused by the stimulating of phage infection. For the infection of T4 phage, the heat output power of single cell increases by 0.49-0.68pW, and the amount of heat produce by single cell is 1.608-1.653 x10-6J.Lysogenic bacteria E. coli (λ) is different from no-lysogenic bacteria bacteria E. coli (λ)- in calorimetric results: In complete medium LBM, the growth rate constant k and the maximum power output Pmax of E. coli (λ)- are both bigger than that of E. coli (λ); in resting medium MM2, the maximum power output Pmax of E. coli (λ)- is bigger than that of E. coli (λ) also. When E. coli (λ)- is infected by A phage, the heat production of host cell can be delayed, and we call this phenomenon as heat production delay (HPD). At high MOI, when E. coli (λ) cells were mixed with A phages, the heat production of lysogenic cells is delayed too. In this thesis, the reasons for these phenomena were discussed. In resting culture, for both of E. coli (λ)- and E. coli (λ), the heat output power P of the resting cells and the total amount of heat Q are increased resulted by A phage infection.Furthermore, we discovered that some small colonies always existed with the normal colonies, when we selected single colony. The small colony is different from the normal colony in sentivity to phage Ml3, thermal power curve of cell infected by M13 phage, and couldn't grow in MM culture medium. This indicated that small colony may lost it's F-pro plasmid, and the growth and multiply be limited in MM culture medium. If this conclusion was true, there would be another infecting and penetrating parthway for Ml3 besides F pilus.In medium LB, there is no difference between M13E system and E. coli JM10... |
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