<p>Kinesin can generally be expressed to high levels in <em>Escherichia coli</em> and this provides an excellent means for obtaining significant amounts of purified constructs. For detailed work, it is essential to have a native construct uncompromised by extraneous tags, and this can readily be obtained. <em>See</em><strong>refs</strong>. 1–3 for examples of vector construction using the T7 RNA polymerase system.</p>