Thank you!! That's a good question! There's really not too many Qs, sadly.

There was a 2022 paper proposing three candidate phyla including Qinglongiota. They seem to be a big fan of oxygen poor environments and sediment!

Mesorhizobium qingshengii is a bacteria associated with milkvetch root nodule, which is cool! Those symbiotic relations are awesome. Everyone says its this cool thing plants can do, because our society suffers from serious metazoan bias, but ALL nitrogen fixation [that we know of] comes from bacteria. Some plants just form these symbioses.

Broadly, there's the concept of Quorum Sensing, which is a huge topic but basically accounts for a ton of the cool stuff bacteria do. Basically they can switch up gene expression based on the proportion of various chemicals in the environment. It is insane and awesome.

I was looking up Q related microbes (that sounds like a horrible conspiracy theory thing oops) and was able to find something tangential — queen bees have a really cool microbiome distinct from other bees!

There's also the queen hypotheses. The "Red Queen" one is general biology, basically just claims evolution is an arms race even if one remains static. Black queen is microbe specific and focuses on why certain traits are lost — basically, bacteria are wont to offload labor they don't need to perform. It's adaptive!