DORMANCY OF BACTERIAL ENDOSPORE 



89 



TABLE III 



COMPARISON OF L-ALANINE ANALOGS AS GERMINATING AGENTS AND SUBSTRATES 



OF L-ALANINE DEHYDROGENASE 



Specificity of alanine dehydrogenase expressed as Vm determined by in- 

 cubating dehydrogenase at 25" with 2 /imoles of DPN and L-alanine 

 analogs, as indicated, in 0.1 M carbonate-bicarbonate buffer, pH 9.4. 

 Reaction rates were measured by spectrophotometric determination of 

 DPNH formation at 340 m^<. 



Substitutions on 

 the ^-carbon 



% Rate of L-alanine 

 Substrate Germination* 



CH 



— CH< 



CH3 

 CH3 



< 



CHj 



OH 



—OH 



— Phenyl 



4.4 







2.5 

 



100 

 65 

 70 

 12 



60 

 60 

 10 









 





* Specificity of germination taken from studies ^^ on B. subtil is germination. 



pounds are non-substrates but germinating agents. The first of 

 these, /5-alanine. also does not complex with the enzyme or 

 inhibit L-alanine oxidation. This is particularly important since 

 Woese et alA^ observed that germination in the presence of 

 /5-alanine is inhibited by D-alanine. 



These differences may be dismissed by the fact that the 

 observations on germination were based on findings with 



References p. 94 



