Final answer:
In bacteria, the formation of loop domains is facilitated by HU proteins, which are responsible for DNA bending and organization of bacterial chromosomes.
Step-by-step explanation:
The proteins that facilitate the formation of loop domains in bacteria are part of a group of proteins that aid in the condensation and structuring of bacterial chromosomes. These proteins are essential for organizing the DNA into compact forms that are necessary for cellular processes such as replication and transcription. In bacteria, the specific proteins responsible for this are known as HU proteins. HU proteins are histone-like DNA-binding proteins that induce the bending of DNA, which in turn facilitates the formation of loop domains aiding in the organization of the bacterial chromosome.