[
Worm Breeder's Gazette,
1979]
To compare enzymatic activities of Bergerac and Bristol strains of C. elegans, we used the microsystem ' Api Zym ' focused by D. Monget ( 1978) and produced by the french firm API SYSTEM. Some of these tests, not yet commercialized, were a gift of API SYSTEM. The technique consists in microdishes which are impregnated with substrate and buffer ( PH is given in the table ). We introduced 0.1 ml of biological suspension ( a known number of adult worms sonicated in buffer and resuspended in distilled water after homogenization ) in the microdishes which were incubated at 37 C for 4 hours. Bacteria were grossly eliminated by washing; Afterwards their concentration was too low to give response with Api Zym. The reactions were revealed colorimetrically by 4 /oo ' Fast blue BB '. The intensity of the reaction is proportional to enzymatic activity and is noted from - to +++++ . A reaction noted +/- refers to a low but detectable response. To give reliable results, all the tests were read by the same experimenter and enzymatic activities in Bergerac and Bristol strains were performed at the same time. To date, the tests were carried out on 64 enzymatic activities. Most of the enzymes tested were hydrolases ( phosphatases,esterases, aminopeptidases, glycosidases, arylsulfatases ) and some were dehydrogenases. Some of the enzymatic activities tested seem to take a prominent part in postembryonic development. It's the case of Leucine arylamidase, which plays an important part in molting ( Rogers 1965, 1977 ), and could be also the case of glycyl-L-proline arylamidase which is implicated in the metabolism of collagen. The results are summarized in the following table. The two strains show similar enzymatic spectra, but differences can be noted, which are localized essentially on : - Trypsin ( n 8 ) - gamma L-glutamate transpeptidase ( n 38 ) - Glycyl-glycine arylamidase ( n 42 ) - L-threonine arylamidase ( n 54 ) - N-CBZ-glycyl-glycyl-L-arginine arylamidase ( n 56 ) Other differences, in a less degree, but yet detectable, are observed on: - Alkaline Phosphatase ( n 1 ) - L-histidine arylamidase ( n 33 ) - L-leucyl-glycine arylamidase ( n 45 ) - L-ornithine arylamidase ( n 51 ) - L-serine arylamidase ( n 53 ) All the differences observed in this table have been verified in two repetitions, which have similar results. But it could be argued that these differences could be due to nutritional adaptation, because these two strains, xenically cultured on the A1 medium ( for thirty years in case of Bergerac, and one year in the case of Bristol ) are associated with a different bacterial complex. [See Figure 1]