3t2w

Publication Abstract from PubMed

Shwanavidin is an avidin-like protein from the marine proteobactrium Shewanella denitrificans, which exhibits an innate dimeric structure while maintaining high affinity towards biotin. A unique residue (Phe-43) from the L3,4 loop and a distinctive disulfide bridge were shown to account for the high affinity towards biotin. Phe-43 emulates the function and position of the critical intermonomeric Trp that characterizes the tetrameric avidins but is lacking in shwanavidin. The 18 copies of the apo monomer revealed distinctive snapshots of L3,4 and Phe-43, providing rare insight into loop flexibility, binding-site accessibility and psychrophilic adaptation. Nevertheless, as in all avidins, shwanavidin also displays high thermostability properties. The unique features of shwanavidin may provide a platform for the design of a long-sought-after monovalent form of avidin, which would be ideal for novel types of biotechnological application.

Structural Adaptation of a Thermostable Biotin-Binding Protein in a Psychrophilic Environment.,Meir A, Bayer EA, Livnah O J Biol Chem. 2012 Apr 5. PMID:22493427^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.