Although animal cell culture has dominated the biopharmaceutical industry for some years now, microbial expression remains important for producing proteins that don’t require posttranslational modifications — or only those that prokaryotic microbes can perform. It also offers an affordable option for antibody fragments and gene therapies. Microbes may be less fragile than animal cells, and they do require simpler media, but they present other challenges related to temperature management and oxygen transfer in culture. Wherever practical, bacterial expression is preferred…