My new prep of competent B. subtilis worked well. The transformation frequencies to Trp+ and Met+ were 1.4x10^-2 and 4x10^-3 respectively. The frequency of Trp+ Met+ double transformants was 2.9x10^-4, indicating that about 20% of the cells are competent. The higher transformation frequencies may also be because I'm using a new prep of the donor DNA, not the 20-year-old prep I used the first time.
I froze most of these cells, and will use some today in more tests of how cells and beads bind to my poly-L-lysine coated coverslips.
Sixty-four years later: How Watson and Crick did it
20 hours ago in The Curious Wavefunction