LYASE, THIAMINE DIPHOSPHATE-DEPENDENT ENZYME, ALPHA-BETA FOLD, HOMODIMER, DIHYDROTHIACHROMINE FORM OF THIAMINE DIPHOSPHATE 3AHG H64A MUTANT OF PHOSPHOKETOLASE FROM BIFIDOBACTERIUM BREVE COMPLEXED WITH A TRICYCLIC RING FORM OF THIAMINE DIPHOSPHATE