Hello!
I found in Fundamentals of Biochemistry by Gajera, H. P. Patel, S. V. Golakiya, B. A. that:
'A variety of other elements are required by at least a few organisms, and
these are B, F, AI, Ti, V, Cr, Ni, Ga, As, Se, Br, Mo, Sn and I.' (page 4)
Anyone knows what are they used for? The rest is quite sensible for me.