Dear Editor, Cobalamin, also known as vitamin B12, can only be biosynthesized by certain
bacteria and archaea. As an essential nutrient for humans, it should be obtained from daily …

Vitamin B 12 (cobalamin) is an essential micronutrient for human health, and mutation and
dysregulation of cobalamin metabolism are associated with serious diseases, such as …

Vitamin B 12 (cobalamin (Cbl)), in the cofactor forms methyl-Cbl and adenosyl-Cbl, is
required for the function of the essential enzymes methionine synthase and methylmalonyl …

ATP-binding cassette subfamily B member 7 (ABCB7) is localized in the inner membrane of
mitochondria, playing a critical role in iron metabolism. Here, we determined the structure of …

Dear Editor, Bile is a complex aqueous secretion produced by the liver that facilitates the
digestion of lipids in the small intestine. A group of ATP binding cassette (ABC) transporters …

The outer membranes of Gram-negative bacteria possess transport proteins essential for
uptake of scarce nutrients. In TonB-dependent transporters, a conserved sequence of seven …

Dear Editor, Bile acids are a group of cholesterol-derived physiological surfactants required
for digestion of lipids and fat-soluble vitamins. 1 However, excess of bile acids is detrimental …

We previously demonstrated that ABCD4 does not localize to peroxisomes but rather, the
endoplasmic reticulum (ER), because it lacks the NH2-terminal hydrophilic region required …

Crystals of the apo form of the vitamin B12 and colicin receptor, BtuB, that diffract to 1.95 Å
have been grown by the membrane-based in meso technique. The structure of the protein …

The human ATP-binding cassette (ABC) transporter ABCB6 is involved in haem-precursor
transport across the mitochondrial membrane. The crystal structure of its nucleotide-binding …