Joining existing overlapping joists

I am doing some kitchen renovations and I want to take 1 side of brick cupboard out. The cupboard is situated in the centre of the down stairs and has the central load bearing wall running through it. I have made some small exploratory holes and found that both sides of the cupboard support joists 3 in total the wall I wish to remove is carrying the overlap. My question is this could I simply bolt the existing overlap together and remove the wall. And if so how many points would I need to fix. The distance to next load bearing wall is approx 600mm.