Fig. 3: Assimilatory nitrite reductase metabolic role, mutations, and nitrogen utilization of mutants.

A Role of the assimilatory nitrite reductase enzyme encoded by nasD in the nitrate assimilatory pathway of S. aureus. Adapted from BioCyc. B Location of missense mutations along NasD protein. Pfam protein domains are shown in distinct colours. C Growth curves of S. aureus nasD/nirB knock-out, ureG knock-out, comEB knock-out (control) and JE (control) strain under the following nitrogen sources: negative control well, nitrite, ammonia, and urea. D Growth curves of S. aureus nasD/nirB p.Cys452Ser mutant, wildtype (i.e. quasi-isogenic isolate lacking the nasD/nirB mutation from the same host) and controls strains under the same nitrogen sources. Coloured lines represent mean OD600 calculated across three replicates, and shaded coloured regions the standard deviation. See Supplementary Data 5 for all mutations identified between colonising isolates of the same host. Source data are provided as a Source Data file.