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Updated: Jul 7, 2026

A Micropatterning Assay for Measuring Cell Chirality
Published on: March 11, 2022
Vibrational circular dichroism analysis reveals a conformational change of the baccatin III ring of paclitaxel:
Hiroshi Izumi1, Atsushi Ogata, Laurence A Nafie
1National Institute of Advanced Industrial Science and Technology (AIST), AIST Tsukuba West, 16-1 Onogawa, Tsukuba, Ibaraki 305-8569, Japan. izumi.h@aist.go.jp
Abstract:
The comparison between measured and conformer-weighted calculated VCD spectra of the baccatin III ring of paclitaxel and visualization of the conformations using the new code for structure-activity relationships are reported for the first time. The VCD spectrum of paclitaxel closely resembles that of the baccatin III ring. The large characteristic nuCO VCD bands with bisignate signs (1732 cm-1, Deltaepsilon = -1.6 x 10(-1); 1715 cm(-1), Deltaepsilon = 2.4 x 10(-1)) strongly reflect the structural property of the family of conformations bacc-ABC32F defined using the new code. The comparison with the conformation of the baccatin III core in the electron micrograph of the crystal structure of tubulin-paclitaxel (1JFF) suggests a conformational change of paclitaxel corresponding to a switch through the binding with beta-tublin and the intermolecular interactions involving the hydroxyl group (D) and carbonyl of acetoxy group (E). The representation of conformational codes allows complicated conformations to be very easily compared and facilitates future computational analyses such as those for the large-molecule calculations as well as genome analysis.
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