Table 1. Loss of Function Mutations in Y. pestis that Enabled Flea-borne Transmission.
| Gene | Gene IDa | Mutation in Y. pestis | Effect | Occurrenceb |
|---|---|---|---|---|
| PDE2 (rtn) | YPTB1308 y2909 | frameshift (6A→7A) in ORF | N-terminal truncation eliminates signal peptide sequence and phosphodiesterase activity; increased c-di-GMP levels | all Y. pestis |
| PDE3c | YPTB3308 y3389 | a) point mutation (C→T) in promoter region (PDE3-pe' allele) | decreased transcription (cf. Fig. S3B) | some Y. pseudotuberculosis (e.g. YPIII) and Y. pestis Branch 0 strains Pestoides A (0.PE4b) and Microtus 91001 (0.PE4c) |
| b) PDE3-pe' mutation plus point mutation (nonsense) in ORF (PDE3-pe allele) | N-terminal truncation eliminates transmembrane domain and phosphodiesterase activity; increased c-di-GMP levels | all Y. pestis except Branch 0 strains Pestoides A (0.PE4b) and Microtus 91001 (0.PE4c) | ||
| c) deletion | no PDE3 phosphodiesterase activity | Y. pestis Branch 0 strains Pestoides F (0.PE2a) and Angola (0.PE3a) | ||
| rcsA | YPTB2486 y1741 | 30-bp internal duplication in ORF* | 10 amino acid tandem repeat insertion, eliminates RcsAB repression of hmsT diguanylate cyclase gene | all Y. pestis except Branch 0 strain Pestoides A (0.PE4b) |
a
Gene annotation numbers for Y. pseudotuberculosis IP32953 and Y. pestis KIM homologs
b
Cf. Figure 5;
c
See Figure S3A for PDE3 allele details
*
Two Branch 1 Y. pestis strains, 1.ANTa (Antiqua) and 1.ANTb (UG05), have a transposon (Tn) insertion in rcsA instead of an internal duplication.