[molecular_function] UDP-N-acetyl-D-glucosamine:N-acetylmuramoyl-L-alanyl-D-glutamyl-meso-2,6-diaminopimelyl-D-alanyl-D-alanine-diphosphoundecaprenol 4-beta-N-acetylglucosaminlytransferase activity <sep> undecaprenyldiphospho-muramoylpentapeptide beta-N-acetylglucosaminyltransferase activity