PROPERTIES OF CHOLEGLOBIN 



473 



ascorbic acid could not be removed without secondary alterations 

 (1709). 



Choleglobin can be distinguished from sulfhemoglobin by its con- 

 version to cholehemochrome with alkali and dithionite. Sulfhemo- 



TABLE II 



Absorption Bands of Choleheme Compounds " 



" According to I^mberg and co-workers (1709). . 



''Values in parentheses are weak bands. It is doubtful whether this band is that of 

 ferricholeglobin; it may 1)6 due to accompanying hem/globin or to ferrochole- 

 globin, ascorbic acid being still present. 



'"According to Kiese and Kaeske (1527). 



globin yields protohemochrome under these conditions, with disap- 

 pearance of the band in the orange part of the spectrum.* 



The absorption spectra are quite different from those of verdo- 

 hemoglobin. Like the latter, however, choleglobin does not absorb 

 strongly in the ultraviolet. Conversion of 20% of hemoglobin into 

 choleglobin is accompanied by a corresponding decrease of the Soret 

 band (ISU)- 



Kiese and Kaeske (1527) have shown that myohemoglobin forms 



corresponding m^^ocholeglobin compounds. Their absorption bands 



* Whereas Liebecq (17S8h) noted a partial reconversion of pseudohemoglobin into 

 protohemochrome, but in later experiments (17JSe) could not obtain conclusive 

 evidence for this, we have recently found (1699) that, under more vigorous conditions 

 (in hot alkaline solution in the presence of reducing agents), cholehemochrome (not, 

 however, verdohemochrome) can be reconverted to protohemochrome. 



