The Gram-negative bacterium E. coli is the host of choice for a multitude of used recombinant proteins. Generally, cultivation is easy, media are cheap, and a high product titer can be obtained. However, harsh induction procedures using isopropyl β-d-1 thiogalactopyranoside as inducer are often referred to cause stress reactions, leading to a phenomenon known as "metabolic" or "product burden"....

Lactose is typically produced via cooling crystallization either from whey(-permeate) (edible-grade) or aqueous solution (pharmaceutical-grade). While in solution, lactose present 2 anomeric forms, α- and β-lactose. During under standard process conditions, only α-lactose crystallizes, depleting the of α-anomer. In practice, mutarotation kinetics are often assumed to be much faster than crystal...

Despite the considerable variation in milk composition found among mammals, a constituent common across all groups is lactose, the main sugar and osmole in most eutherians milk. Exceptions to this are the families Otariidae (fur seals and sea lions) and Odobenidae (walruses), where lactose has not been detected. We investigated the molecular basis for this by cloning alpha-lactalbumin, the modi...

Lactose intolerance has been reviewed in published statements by the Protein Advisory Group of the United Nations System,’ the Food and Nutrition Board of the National Research Council,2 and the American Academy of Pediatrics, Committee on Nutrition.’ Each of these statements deals principally with the advisability of encouraging population groups with a high rate of lactose intolerance to cons...

Mutations in the lacY gene of Escherichia coli have been used to analyze the functional organization of lactose permease. Deletions suggest that the NH2 terminus of lactose permease is not essential and can be replaced by residues of the cytoplasmic enzyme beta-galactosidase. Negative dominant mutations in the lacY gene can be explained by the assumption that membrane-associated lactose permeas...

Lactose intolerance has been reviewed in published statements by the Protein Advisory Group of the United Nations System,’ the Food and Nutrition Board of the National Research Council,2 and the American Academy of Pediatrics, Committee on Nutrition.’ Each of these statements deals principally with the advisability of encouraging population groups with a high rate of lactose intolerance to cons...