The Isolation, Purification and Properties of Haemin a 329 



SUMMARY 



1. A method for the preparation of unaltered porphyrin a and haemin a 

 from heart muscle is given. 



2. Evidence is adduced to show that haem a is the prosthetic group of the 

 cytochromes a, a^ and a^. 



3. Determinations of the haem a content of tissues as porphyrin a or 

 pyridine haemochrome a are described and their limitations are discussed. 



4. Spectroscopic properties of haem a compounds with nitrogenous bases, 

 cyanide, and native and denatured proteins, as well as their carbon monoxide 

 compounds are investigated. The properties of these proteins and their 

 carbon monoxide compounds are compared with the properties of the 

 cytochromes a, a^ and ^3. 



ADDENDUM 



This paper was completed before we became aware of the recent work of 

 Kiese and Kurz (1958). The German authors have also found the shift of the 

 a-absorption bands of the haemoproteins a to longer wavelengths by carbon 

 monoxide, and the peculiar denatured protein haemochromes. There are 

 small discrepancies, e.g. in the position of the oc-bands of ferrohaemoglobin 

 a and ferrohaemalbumin a. 



Acknowledgement 



This research has been carried out with grants from the National Health 

 and Medical Research Council of Australia. 



REFERENCES 



Chance, B. &. Yonetani, T. (1959). Fed. Proc. 18, 202. 



Dannenberg, H. & Kiese, M. (1952). Biochem. Z. 322, 395. 



Fox, H. M. (1924). Proc. Canib. Phil. Sac. {Biol. Sci.) 1, 204. 



Granick, S. (1952). Fed. Proc. 11, 221. 



Kiese, M. & Kurz, H. (1954). Biochem. Z. 325, 299. 



Kiese, M. & Kurz, H. (1958). Biocliem. Z. 330, 177. 



Lemberg, R., Falk, J. E., Rawlinson, W. A., Hale, J. H. & Rimington, C. (1949). 



Abstr. Comm. \st int. Congr. Biochem., Cambridge p. 351. 

 Lemberg, R. & Falk, J. E. (1951). Biochem. J. 49, 674. 

 Lemberg, R. (1953). Nature, Lond. 172, 619. 

 Lemberg, R. (1955). Biochemistry of Nitrogen, p. 165. Helsinki: Suomalainen Tiede- 



akatemia. 

 Lemberg, R., Bloomfield, B., Caiger, P. & Lockwood, W. H. (1955). Aust. J. exp. 



Biol. med. Sci. 33, 435. 

 Lemberg, R. & Stewart, M. (1955). Aust. J. exp. Biol. med. Sci. 33, 451. 

 Lemberg, R., Morell, D. B., Lockwood, W. H., Stewart, M. & Bloomfield, B. (1956). 



Chem. Ber. 89, 309. 

 Lemberg, R. & Benson, A. (1959). Nature, Lond. 183, 678. 

 Morell, D. B. & Stewart, M. (1956). Aust. J. exp. Biol. med. Sci. 34, 211, 

 Morrison, M., Connelly, J. & Stotz, E. (1958). Biochim. biophys. Acta Tl, 214. 

 Oliver, L T. &. Rawlinson, W. A. (1951). Biochem. J. 49, 157. 

 Parker, J. (1959). Biochim. biophys. Acta 35, 496. 



