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H. J. CORPER AND H. C. S WE ANY 



after incubation 0.5 cc. amounts were withdrawn and also 

 analyzed for methyl alcohol soluble amino acid a nitrogen 

 content. In making the analyses the amount of amino acids 

 was always compared with a- fresh solution of asparagin as 

 standard (0.0317 mgm. amino acid a nitrogen as asparagin) 

 and the figures given are in milligram amino acid a nitrogen 

 as derived from this standard. 



Summary. The autolysate from tubercle bacilli possesses an 

 enzyme capable, in 0.2 per cent hydrochloric acid solution, of 

 splitting a completely methyl alcohol precipitable peptone 

 prepared from Witte's peptone into simple amino acid a nitrogen 

 compounds, not precipitable by this means. 



Series IV. Nuclease {nucleic acid splitting enzyme) 



Experiment I. Nephelometrically. To the autolysate (twenty- 

 four hours in incubator under toluene) obtained from a heavy 

 suspension of tubercle bacilli (2 cc. bacillary residue) in sterile 

 physiological salt solution, was added (to a test and heated 

 control) 1 cc. 0.1 per cent nucleic acid making a total of 6 cc, 

 and 2 cc. toluene and 1 cc. chloroform. The nucleic acid was 

 determined quantitatively by the nephelometric method of 

 Kober. In this preliminary test the heated control was used as 

 the standard and the results obtained in percentage as compared 

 to heated control, were; immediately — 100 per cent nucleic 

 acid; three days — 80 per cent nucleic acid; and six days 77.5 

 per cent nucleic acid. 



This experiment was then repeated more elaborately in that 

 both the heated control and test were compared with a freshly 

 prepared standard of nucleic acid each time. The standard 



