Eight strains (seven species) of Neisseria were found to possess intracellular amylosucrases capable of synthesizing glycogen directly from sucrose. All eight systems were stimulated by primer glycogen, possessed similar kinetic parameters, and were competitively inhibited to similar degrees by fructose. The enzymes bound tightly to their polysaccharide products but these complexes could be readily dissociated by polyacrylamide gel electrophoresis. Some of the enzyme-product complexes appeared to be virutally free of contaminating proteins.