224 1. MALONATE 



Salmonella enteritidis but this is not due to a decrease in the number of 

 leucocytes (Yamauchi, 1956). The survival times of chicks infected with 

 Salmonella pullorum are reduced by 500-800 mg/kg of malonate injected 

 simultaneously or shortly after the bacterial inoculation (Gilfillan et al., 

 1956). On the other hand, the diethyl ester of malonate increases the sur- 

 vival time of mice infected with Mycobacterium, tvbercvlosis, when admin- 

 istered daily for 2 weeks at oral doses of 250-500 mg/kg (Davies et al., 

 1956). Compounds of this type are thus considered worthy of study as 

 chemotherapeutic agents in tuberculous infections. 



METABOLISM OF MALONATE 



Malonate occurs normally in many types of organism and occasionally 

 at concentrations possibly inhibitory to succinate dehydrogenase. Many 

 organisms are capable of metabolizing malonate by various pathways and 

 some are able to utilize it for growth or cell functions. In some cases, in- 

 deed, it is difficult to demonstrate the inhibitory action of malonate in the 

 presence of its own oxidation. The metabolism of malonate must always be 

 considered in studies of the effects of malonate on any type of cellular ac- 

 tivity. It is often impossible to detect and correct for the metabolism of 

 malonate without using labeled malonate. It is possible that many studies 

 of the inhibition of respiration or cycle activity by malonate have been 

 complicated by the oxidation of the malonate. 



Occurrence of Malonate 



Malonate has been isolated or demonstrated chromatographically from a 

 number of microorganisms, plants, and animals, and it is likely, consider- 

 ing the recent demonstration of its role and the role of malonate derivatives 

 in fatty acid metabolism that its occurrence is widespread. The accom- 

 panying incomplete tabulation will serve to illustrate this. Malonate has 

 also been found in winter wheat, barley, oats, alfalfa, kidney bean leaves, 

 clover, pea leaves, vetch leaves (Soldatenkov and Mazurova, 1957), sake 

 (Kawano and Kawabata, 1953), and several products prepared from plants. 

 Although no thorough studies of animal tissues have befen made, it is 

 evident that malonate must occur in rat, dog, and human tissues to some 

 extent if it is found in the urine. Although the name of malonate comes 

 ultimately from the Latin mains, it has never been identified in apples 

 or other fruit. 



Methylmalonate has been found in Propionibacterium (Stjernholm and 

 Wood, 1961; Wood and Stjernholm, 1961), pigeon liver (Bressler and Wakil, 

 1961), pig heart (Flavin et al., 1955), mouse adipose tissue (Feller and Feist, 

 1957), and rat and human urine (Boyland and Levi, 1936; Barness et al., 



