Table 4.
Expression of biosynthetic genes for antifungal metabolites during insect infection by Pseudomonas protegens CHA0.
| 16s | ofaA | phlD | fitD | prnD | hcnA | pltA | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| i | o | i | o | i | o | i | o | i | o | i | o | i | o | |
| 20 h | 3 | 3 | 0 | 0 | 3 | 0 | 3 | 1 | 2 | 2 | 3 | 1 | 3 | 1 |
| 30 h | 3 | 3 | 3 | 2 | 2 | 0 | 3 | 3 | 2 | 3 | 3 | 2 | 3 | 1 |
| Dead | 3 | 3 | 3 | 3 | 3 | 3 | 3 | 3 | 3 | 3 | 3 | 3 | 3 | 3 |
Galleria mellonella larvae were infected systemically by injection (i) of 2 × 103 cells of P. protegens CHA0 into the hemocoel. Plutella xylostella larvae were infected orally (o) by feeding artificial diet inoculated with 4 × 106 cells of P. protegens CHA0. For G. mellonella infections, hemocoel was collected 20 and 30 h post injection (living larvae) and after 42 h when larvae had succumbed to infection (Dead). For P. xylostella infections, entire larvae were collected after 20 and 30 h and when death occurred (Dead). Total RNA was extracted from insect tissue, converted into cDNA and gene expression for the indicated genes was checked by PCR. Because results for some of the genes varied, a summary of the outcome of three experiments is presented and numbers indicate how many times (out of three) expression of the respective gene was detected. A Pseudomonas specific primer for the 16s rRNA gene was used to detect presence of the bacteria. In non-infected control larvae, neither expression of the Pseudomonas 16s rRNA gene nor of any of the other genes was detected. For each gene and insect system one representative gel is shown in Supplementary Figure S3.