Catalyzes the transglycosylation of maltooligosaccharides, yielding maltooligosaccharides of various lengths and glucose. Maltose and glucose can be used as acceptors in the transfer reaction. Transfers a segment of a (1->4)-alpha-D-glucan to a new position in an acceptor, which may be glucose or a (1->4)-alpha-D-glucan. Inhibited by p-chloromercuribenzoic acid, monoiodoacetic acid, mercury and nickel ions. Optimum temperature is 85-100 degrees Celsius. homodimer. Expressed constitutively. Belongs to the glycosyl hydrolase 57 family.