Q: WHAT can be done about a negative review that I might receive on Google Plus?
A: Unless the review is defamatory, otherwise unlawful or violates Google’s own policies, and you can prove it without attracting even more negative attention and incurring considerable costs, there may not be much that can be done about it.
That said, you may be able to report the review/comment to Google. Whether it will do anything about it in a timely fashion or at all remains to be seen, and each case will of course turn on its own merits.
Google’s relatively new Contact Us process appears to offer an improvement in elevating a form to contest reviews. The form sends a review removal request into the queued email response system and, typically, generates an intelligent response from a human. This contrasts with the review flagging process more typically encouraged.
In the field asking for content of the inappropriate review, add suitable comment. There is also now an option to ask for them to be moved from one listing to another. If all else fails, it may be possible to push down the negative comment and effectively have it buried.
Since less than one per cent of all searches go past the second page of search results this is worth considering.