ENERGY YIELDING PROCESSES 



GLUCOSE- 1 - P • 



GLYCEROL 

 I ATP 



Iglucose] 



I ATP 

 -GLUCOSE -6- P 



3 KETG- 

 .6-P-GLUCONATE 

 fTPN -C02| 

 •6-P-GLUCONATE '- 



^ XYLULOSE-P 



GLYCEROL- P---Di (OH) ACETONE -P-= ^ IGLYCERALDEHYDE"^ " 



DPN TT 



1 Pi, GSH, DPN 



1,3-Di-P-GLYCERIC 



CHOLINE 

 ETHANOL- NH, 



|3-P-GLYCERic] -— 



I 



2-P GLYCERIC 

 , 1 



|P-enol-PYRUVIC| - 



SERINE 

 GLYCINE 

 CYSTEINE 



AMP 

 GMP 



PHENYLALANINE 



TYROSINE 



TRYPTOPHANE 



PABA 



PHBA 



OH-PROLiNE Jcc -KETOGLUTARATEl succinate 



GLUTAMINEI > CoA, DPN, 



I GDP-C02 



IporphyrinI iSUCCINYL-CoAh - 



Fig. I. Relationship between glycolytic, pentose and tricarboxylic acid cycles and amino 



acids, vitamins and nucleotides. 



boxylated to acetyl-CoA. Consequently, the level in the metabolic sequence 

 designated by pyruvate and the other already mentioned metabolites, may be 

 thought of as important points of bifurcation in the metabolic highways. At each 

 of these points the compound in question may be metabolized by the cell along 

 catabolic pathways or the metabolism may be diverted along metabolic path- 

 ways which lead to growth. 



The relation between pyruvate, a-ketoglutarate, the other key metabolic inter- 

 mediates and various amino acids, vitamins, and nucleic-acid constituents, is also 

 shown in Fig. i. This relationship will be discussed in more detail later. 



B. The Catabolism of Glucose and Fatty Acids 

 I. The Embden- Meyerhof glycolytic sequence 



The substances normally catabolized by a given cell vary with the inherent capa- 

 bilities of the cell and the exigencies of the food supply. Since glucose and its 



Literalure p. 1 24 



