Is there a way to correct this waste of gutter space?

I recently began experimenting with a vertical monitor - IE turned 90°.  I noticed that PyCharm wastes a LOT of horizontal space on the line numbers:

Since the monitor is tilted, horizontal space is at a premium for me.

(This screensnip is the entire width of the screen - yes, that's it)

Can I adjust the size of this gutter?  What a waste of whitespace.