What adaptations did bacteria involve that were essential for the evolution of multicellularity?

Generally speaking, bacteria reproduce by fission, which means that they split in two. When a bacterium reaches a sufficient size, it splits, resulting in two new bacteria identical to the parent cell. In turn, these two bacteria split, and so on. This phenomenon occurs at regular intervals, the time required varying greatly from one species to another, and depending upon environmental conditions. For example, if it is placed in ideal conditions, a marine bacterium called Pseudomonas natriegens splits every 10 minutes, whereas the tuberculosis microbe (Mycobacterium tuberculosis) splits only every 27 hours.
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