Catalytic subunit of cellulose synthase. It incorporates glucose from uridine 5'-diphosphate glucose (UDP-alpha-D-glucose) to cellulose (a (1->4)-beta-D-glucan), which is produced as an extracellular component for mechanical and chemical protection at the onset of the stalk formation, when the cells exhibit multicellular behavior during culmination. [(1->4)-beta-D-glucosyl](n) + UDP-alpha-D-glucose = [(1->4)-beta-D-glucosyl](n+1) + H(+) + UDP Glycan metabolism; amoeba cellulose biosynthesis. Progressively accumulates during culmination, especially at the onset of the stalk formation. Present in fruiting body (at protein level). There are two conserved domains in the globular part of the protein: the N-terminal domain (domain A) contains the conserved DXD motif and is possibly involved in catalysis and substrate binding. The C-terminal domain (domain B) contains the QXXRW motif and is present only in processive glycosyl transferases. It could be involved in the processivity function of the enzyme, possibly required for holding the growing glycan chain in the active site. Amoebae missing dcsA exhibit snowmen-shaped fruiting bodies. Belongs to the glycosyltransferase 2 family.