Table 9. Effects of temperature on the metabolism of four 



different organic substrates by micro-organisms sampled from 



Pele's Vent. The data are presented either as total amounts 



of radioactivity incorporated into acid insoluble cellular 



"3 "3 "3 



materials (°H-adenine, °H-thymidine, °H-glutamate ) or as 



respired plus incorporated radioactivity ( l^C-acetate and 



l^C-methane ) . The values given in parentheses indicate the 



percentage of the total metabolic activity relative to the 



maximum rate observed for that particular substrate. 



- Total Radioactivity, pCi per ml -1 



Substrate 1 4°C 25°C 37°C 60°C 



14 C-acetate 21.3 43.3 886.8 33.2 



(2.4%) (4.9%) (100%) (3.7%) 



3 H-adenine 122.2 253.5 445.0 364.3 

 (27.5%) (57.0%) (100%) (81.9%) 



3 H-glutamate 79.7 332.8 732.2 888.8 



(9.0%) (37.4%) (82.4%) (100%) 



3 H-thymidine 32.5 306.2 708.6 563.5 



(5.8%) (43.2%) (100%) (79.5%) 



1 Details of the site of labeling, specific radio- 

 activities and experimental design are given in 

 the text. 



218 



