Abstract：
:X-ray fiber diffraction is one of the most useful methods for examining the structural details of live biological filaments under physiological conditions. To investigate biologically active or labile materials, it is crucial to finish fiber alignment within seconds before diffraction analysis. However, the conventional methods, e.g., magnetic field alignment and low-speed centrifugations, are time-consuming and not very useful for such purposes. Here, we introduce a new alignment method using a rheometer with two parallel disks, which was applied to observe fiber diffractions of axonemes, tobacco mosaic tobamovirus, and microtubules. We found that fibers were aligned within 5 s by giving high shear flow (1000-5000 s(-1)) to the medium and that methylcellulose contained in the medium (approximately 1%) was essential to the accomplishment of uniform orientation with a small angular deviation (<5 degrees). The new alignment method enabled us to execute structure analyses of axonemes by small-angle x-ray diffraction. Since this method was also useful for the quick alignment of purified microtubules, as well as tobacco mosaic tobamovirus, we expect that we can apply it to the structural analysis of many other biological filaments.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Sugiyama T,Miyashiro D,Takao D,Iwamoto H,Sugimoto Y,Wakabayashi K,Kamimura Sdoi
10.1016/j.bpj.2009.09.041subject
Has Abstractpub_date
2009-12-16 00:00:00pages
3132-8issue
12eissn
0006-3495issn
1542-0086pii
S0006-3495(09)01525-2journal_volume
97pub_type
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