Abstract:
:Using a method they developed, Stamatoff and Krimm (1976) have phased swelling data from nerve myelin. Although most phases agree with those I determined previously, there are a few differences. In this letter the two different phasings, theirs and my own, are used to compute the corresponding electron-density profiles, which are then closely compared. For both phasings, small differences are seen in the membrane profile at different degrees of swelling. The explanation that these differences are due simply to errors in measuring intensity is shown to be quite improbable; thus the differences indicate a real change in the profile. It follows that the assumption of a constant membrane profile appears to be invalid in the case of myelin swelling. The differences therefore are assumed to indicate a real change in the profile. It is shown that this change can be attributed consistently to interdigitation of protein molecules at the surfaces of neighboring membranes, while the membrane structure itself remains unchanged. In this case, valid phases still can be determined by swelling, but the phases determined by Stamatoff and Krimm are not valid.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Blaurock AEdoi
10.1016/S0006-3495(79)85242-Xsubject
Has Abstractpub_date
1979-04-01 00:00:00pages
147-55issue
1eissn
0006-3495issn
1542-0086pii
S0006-3495(79)85242-Xjournal_volume
26pub_type
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