Nutritional benefits of natto using soy vs other beans

[bravebird]

hey all,
i'm trying to find out about the vitamin K2 content of traditional soy natto. does the abundance of vitamin K2 come from the presence of the Bacillus natto bacteria alone, or does it come from any reactions the bacteria have with the high vitamin K1 profile of soybeans?
In other words, would making natto out of something other than soy (let's say lentils or something not so high in vitamin K1) have a high vitamin K2 profile?