Schematic diagram of plasmids prepared. Only the inserted DNA regions in each plasmid are illustrated. Thick lines in each plasmid indicate the chromosomal DNA from M. luteus B-P 26, and thin lines indicate parts of the vector, pUC119. Open arrows show the three open reading frames found in the DNA region responsible for expression of HexPS. Abbreviations: H, HindIII; P, PstI; Hi, HincII; X, XbaI; B, BamHI; K, KpnI; S, SacI; E, EcoRI; E14, EcoT14I; N, NruI.