FIG. 5.

Phenotypic analyses of an insertion mutation in mlr5932, a gene that was upregulated during symbiosis. (A) Construction of the mlr5932 insertion mutant D21. A gentamicin cassette (Gm cassette) was inserted into the StuI site of mlr5932. The arrows and arrowhead indicate putative sigma 54 promoters and an upstream activator sequence (UAS), respectively. (B) ACC deaminase activities of wild-type strain MAFF303099 (WT) and mlr5932 insertion mutant D21 in bacteroids and free-living cells. The error bar indicates 1 standard deviation. ND, not detected. (C) Nodulation of L. japonicus MG20 inoculated with wild-type MAFF303099 or the mlr5932 insertion mutant D21. The error bars indicate standard errors. One asterisk and two asterisks indicate significant differences in mean numbers of nodules between the treatments at confidence levels of 0.05 and 0.01, respectively, as determined by Student's t test. (D) Nodulation competitiveness of wild-type strain MAFF303099 and the mlr5932 insertion mutant D21 when MAFF303099(pDG499) was used as a reference strain.