Decomposition of Proteins 167 



iiininoiiiu (Table 34). The enzymes coneeined in these reactions 

 arc known as deaminases and amidases. 



Table 3-t. TuANSFciiniATiox ov Photioin Xithouen' into Ammonia hy IVIicuoouganisms 



Orgaiiisni Per Cent 



B. arborcscens 19 



Ps.fluorescens liquvfaciens 16 



Cephalothecium roseum 37 



A. terricola 32 



Botryotrichum pilulifcnini 24 



Stemp/iylium sp. 5 



Actinomyces sp. 21 



Many proteins are present in \arious residues, especially in micro- 

 bial products, in the form of compounds with nucleic acids, known 

 as nucleoproteins. The composition of a typical protein is NHo- 

 CHRCO(NHCHRCO)„NHCHRCOOH. A typical nucleic 

 acid has the composition C3CH4SO30N4P4 and is made up of a purine 

 or pyrimidine base, a carbohydrate (hexose or pentose), and phos- 

 phoric acid. 



Proteins can be broken down by microorganisms through one or 

 more of the following processes: 



1. Hydrolytic deaminization. The hydrolysis of an amino acid 

 may result in the formation of a lower fatty acid and ammonia; or 

 of an alcohol, COo, and ammonia; or of an aldehyde, lower acid, 

 and ammonia, as shown by the general formulas: 



R CH XH2 COOH + H2O = R CHOH COOH -f NH3 (1) 



R CH • NH2 • COOH + H2O = R CH2OH -f CO2 + NH3 (2) 



R CH XH2 COOH + H2O = R CHO + H COOH -f NH3 (3) 



2. Decarboxylation with amine formation: 



R CH NHo COOH - R CH2 NH2 + CO2 (4) 



R CH2 XH2 + H2O = R CH2 OH + NH3 (5) 



3. Reductive deaminization: 



RCH NH2COOH + H2 = R CH2 COOH -f NH3 (6) 



or 



RCH NH2COOH + H2 = R CH3 + NH3 + CO2 (7) 



