<P/>Some 100 pectolytic bacteria belonging to different genera and species, were obtained by isolation from vegetables and by screening of culture collections. The crude enzyme preparations of 19 of these strains were typed by mutual comparison. Differences in the composition of five commercial fungal 'pectinase' preparations were also studied. Purified endo pectate lyase of Arthrobacter which was studied in detail, appeared to attack pectate far 'less randomly', than endo pectate lyases of Bacillus polymyxa or Pseudomonas. The best substrates for pectate lyases were not pectates but 21 to 44% esterified pectins. A new method for the determination of the number average degree of polymerization of pectic substances was introduced. The literature on pectolytic enzymes was reviewed.