New Cas9 protein from Alkalibacillus strain isolated from Ebeyty lake
In 2024 I visited the hypersaline Lake Ebeity and collected water and sediment samples there. Our student Victoria Ronchikova isolated halophilic archaea and bacteria from these samples. Among the isolates was a halotolerant bacillus, Alkalibacillus sp. S2W, which turned out to be able to grow on medium containing 23% salt. We sequenced its genome and found a gene encoding a Cas9 protein that differs from the ones studied so far. Meanwhile, Bogdan Kirillov had been developing computational methods for identifying PAMs with a minimal number of experiments. Alexandra Vasilieva joined the project as well: she purified the protein derived from our bacillus and used it to validate Bogdan's methods. The methods worked — and now a preprint on this work is out!
