FIG. 3.

Two Coomassie blue-stained SDS-PAGE gels showing secreted proteins from R. leguminosarum bv. viciae mutants. Culture supernatant proteins were precipitated from the prsD mutant A412 (lane b), wild-type (WT) 8401(pRL1JI) (lanes c and d), the plyA mutants A501 (lane e) and A503 (lane f), and the plyB mutant A617 (lane g). Molecular size markers (94, 67, 43, and 30 kDa) are shown in lanes a and h. The strains were grown in the absence of the nod gene inducer hesperetin. Proteins present in 8401(pRL1JI) but absent from the secretion mutant A412 are indicated in lanes c and d. One of these proteins (arrowhead) is apparently also absent from A617 (lane g). The gel containing lanes a, b, and c was run slightly differently from the other gel; the lines highlight the positions of the proteins that were absent from the supernatant of prsD mutants.