220 ANAEROBIC METABOLISM 



organisms in which it received more attention than in 

 other invertebrates. But several degradation processes of 

 amino acids are known which do not require molecular 

 oxygen. They are listed here as given by Stephenson 

 (1939). To investigate whether and to what extent these 

 processes occur in invertebrates would be an interesting 

 field for future study. 



(a) Decarboxylation of the amino acids with forma- 

 tion of the corresponding amine: 



R.CHNHa.COOH-^COs+R.CHaNHa 



(b) Hydrolytic deamination with formation of the hy- 

 droxyacid : 



R.CHNH2.COOH+H2O— NH3+R.CHOH.COOH 



(c) Hydrolytic deamination and decarboxylation with 

 formation of the alcohol: 



R.CHNH2.COOH+2H— >C02+NH3+R.CH20H 



(d) Reductive deamination with formation of the sat- 

 urated acid : 



R.CHNH2.COOH+2H— .NH3+R.CH2COOH 



(e) Reductive deamination and decarboxylation with 

 the formation of the hydrocarbon: 



R.CHNH2.COOH+2H— CO2+NH3+R.CH3 



(f) Deamination and desaturation at the alpha-beta 

 linkage with formation of the unsaturated acid : 



R.CH2.CHNH0.COOH— NH3-fR.CH:CH.C00H 



(g) Mutual oxidation and reduction by pairs of amino 

 acids : 



R.CH2CHNH2.COOH+2R.CHNH2.COOH+2H0O— 

 R.CH2.COOH4-C02-fNH3-K4H-f2R.CHNH2.COOH 

 — R.CH2.COOH-f-C02-fNH3-F2R.CH2COOH+2NH3 



(h) Anaerobic breakdown with production of hydro- 

 gen: 



5C5H9O4N+6H2O— 6CH3.COOH+2CH3(CH2)2 

 .COOH + 5C02 + H2-F5 NH3 



