The substrates (chemcial species that are being observed in a chemical reaction) of Dimethylglycine dehydrogenase are N, N-dimethylglycine, acceptor (electron acceptor of tranfers from other compounds) and H2O.
The 3 substrates of this enzyme are N,N-dimethylglycine, acceptor, and H2O, whereas its 3 products are sarcosine, formaldehyde, and reduced acceptor. In chemistry, a substrate is typically the chemical species being observed in a chemical reaction, which reacts with a reagent to generate a product. An electron acceptor is a chemical entity that accepts electrons transferred to it from another compound. 
