STUDY ON GROWTH AND ADENOSINE NUCLEOTIDES OF MARINE AND TERESTRIAL PSYCHROTROPHIC BACTERIA

1996 Fiscal Year Final Research Report Summary

• Project/Area Number: 07806028
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Fisheries chemistry
• Research Institution: NAGASAKI UNIVERSITY
• Principal Investigator: MORII Hideaki FACULTY OF FISHERIES PROFESDSOR, 水産学部, 教授 (60039724)
• Project Period (FY): 1995 – 1996
• Keywords: PSYCHROTROPHIC BACTERIA / GROWTH / ADENOSUNE NUCLEOTIDES

Research Abstract

The mechanism that organisms can live at low temperature is not clear. Especially, the study for nucleic acid precursors has not been almost performed until this time because the method for the speedy and accurate analysis has not been perfected. The methods for determination of adenylate concentrations in bacterial culture were examined and perfected. Scecondly, marine and terrestrial psychrotrophic bacteria were isolated from cold environments, and growth and change with growth time in adenylate concentrations were studied especially for psychrotrophic Pseudomonas spp. In the results, the psychrotrophic Pseudomonas spp.were divided into two groups on the basis of growth pattern and optimum growth temperature (Group I and II strains having optimum growth temperature below and above 25ﾟC). The two groups were different from effects of magnesium and glucose on growth, production of acid from glucose, utilization of pyruvate etc.as sole carbon source. The level of adenosine nucleotides i n Group I was generally highest in AMP,moderate in ADP,and lowest in ATP during growth, regardless of the growth temperatures. Almost all adenosine nucleotides in Group II were occupied by AMP through the entire growth period, independently of the growth temperatures. The adenylate energy charge (ATP+1/2ADP/ATP+ADP+AMP) during the growth phase was extremely low value (approach to the zero) in Group II.In Group I grown at the temperatures of an optimum temperature or below, adenylate concentrations in the culture increased with elongation of incubation time. In Group II,AMP concentration rose quickly, reached a maximum and then fell abruptly to the base during the logarithmic and stationary phases for growth. The similar results were also recognized in different inorganic and organic media, oxygen tentions, and pHs. These results suggest that Groups I and II are different evolutional groups, and that the growth at low temperature in psychrotrophic bacteria is connected with adenylate metabolisms.