498 



APPENDIX 



The extinction coefficient of BChl in ether at 773 mju (Table 2) is 

 based on Weigl's value (1) of 96 mM-lcm-1. The values for BChl in 

 acetone/methanol and in vivo were obtained by direct comparison with 

 BChl in ether (R. K. Clayton, unpublished). The extinction values 

 serving as ordinate in Figs. 6 and 7 are in units of liters per gram-cm. 

 They differ from €(mM-lcm-l) by a factor of 1000/Mol,Wt, The mo- 

 lecular weights of BChl and bacteriopheophytin are 911 and 889 re- 

 spectively (2), Those of the chlorobium chlorophylls are not known. 



Abundant references can be found in reviews by Smith and Benitez 

 (2) and Smith and French (3). 



TABLE 1. 



Infrared Absorption Maxima of the Chlorophylls of Photosynthetic Bacteria 



T-, r TT * o Absorption Maxima in m.n 



Reference Pigment Source . ^. • *u 



'^ m VIVO in ether 



TABLE 2. 



Extinction Coefficients of BChl in vitro and in vivo 



For the Soret band in vivo, at 375 m^, the millimolar extinction coefficient is 

 100 + 10 (1 cm path). 



Wavelength, m/y 



e, mM ^cm 



