AMINO ACIDS AND MICRO-ORGANISMS 
541 
Amino Acid 
Decomposition Products 
Yeasts 
Bacteria 
glycine 
<3 — alanine 
d. — valine 
1 — leucine 
d — isoieucine 
1 — tyrosine 
1 — phenylalanine 
1 — cystine 
1 — serine 
1 — aspartic acid 
d — glutamic acid 
d — arginine 
1 — histidine 
lysine 
1— proline 
1 — tryptophan 
phenylglycine 
isovaline 
methyl alcohol, 
acetic acid 
acetaldehyde, alcohol 
isobutyl alcohol 
isoamyl alcohol 
d — : amyl alcohol 
p — oxyphenylethyl alcohol 
(tyrosol) 
Phenylethyl alcohol 
ethylene glycol 
succinic acid 
succinic acid 
tetramethylene diamine, 
guanidine 
imidazolylethyl alcohol 
indolethylalcohol 
tryptophol 
benzylalcohol 
butvl alcohol 
acetic acid, CO., 
valeric acid, isobutylamine 
isoamylamine 
caproic acid, valeric acid 
d — caproic acid 
p — oxyphenylethylamine 
(tyramine) 
p — oxyphenylpropionic acid 
p — oxyphenylacetic acid 
p — cresol, phenol 
hydrocinnamic acid 
phenylacetic acid 
(C 2 H r ) 2 S, QH..SH, H 2 S 
propionic acid 
3 — alanine 
succinic, propionic, 
formic acids 
y — amino butyric acid 
butyric, formic acids 
ornithine 
8 — amino valeric acid 
tetramethylene diamine 
3 — imidazolylethylamine 
I midazolpropionic acid 
pentamethylene diamine 
amino valeric 
n — valeric acid 
indolpropionic, indolacetic 
skatol, indol 
indol-ethylamine 
The products formed by yeasts and by bacteria are considered 
separately for purposes of comparison. Some gaps will be noted 
in the table, but the data are on the whole sufficiently com- 
plete to give an idea of the dominant reactions. Some anoma- 
lies will be found, but considering the fact that the data were 
secured by different investigators working with different or- 
ganisms and under varying conditions, the uniformity is really 
surprising. 
YEASTS. 
First let us consider the products formed by yeasts. Out of 
the fourteen amino acids on which data are available, eleven 
give rise to an alcohol with one less atom of carbon. The reac- 
tion probably proceeds in three stages, as follows: (1) hydrol- 
ysis of the amino acid into' ammonia and the corresponding 
hydroxy-acid, (2) cleavage of the hydroxv-acicl into the next 
lower aldehyde and formic acid, (3) reduction of the aldehyde 
to the corresponding alcohol. The fact that traces of the alde- 
hyde - and formic acid have in some cases been demonstrated as 
