Carbohydrate transport in bacteria under environmental conditions, a black box?

A typical eubacterium carries a battery of substrate transport systems which are the ultimate pacemakers for growth. These systems reflect a billion year old selection for coping with rapidly changing conditions in the environment and each of them is optimised for specific growth conditions. Metabolic pathways in combination with transport systems can be interpreted as transient sensory systems, where a transport system corresponds to a sensor for external stimuli. Characteristics is a tightly linked common control between a carbohydrate metabolic pathway and the corresponding transport system. Many of the observed growth phenomena are a direct result of adaptation and regulation of transport capacity to rapid changes in environmental conditions. Some of the better understood examples are discusses. Nevertheless, knowledge on bacterial carbohydrate transport under environmental conditions as documented in the literature is still scarce.