This is a commentary on three recent reports in Nature journals regarding magnetism in biological systems. The first claims to have identified a protein complex that acts like a compass needle to guide magnetic orientation in animals (Qin et al., 2016). Two other articles report creation of a magnetically-gated ion channel by attaching ferritin to an ion channel and pulling on the ferritin with a magnetic field (Stanley et al., 2015; Wheeler et al., 2016). Here I argue that these claims are in conflict with basic laws of physics taught in college . The discrepancies are large: from 5 to 10 log units. If the reported phenomena do in fact occur, they must have causes entirely different from the ones proposed by the authors. One can conveniently analyze these reports with the same back-of-the-envelope calculations .
This is an analysis of how magnetic fields affect biological molecules and cells. It was prompted by a series of prominent reports regarding magnetism in biological systems. The first claims to have identified a protein complex that acts like a compass needle to guide magnetic orientation in animals (Qin et al., 2016). Two other articles report creation of a magnetically-gated ion channel by attaching ferritin to an ion channel and pulling on the ferritin with a magnetic field (Stanley et al., 2015; Wheeler et al., 2016). Here I argue that these claims are in conflict with basic laws of physics . The discrepancies are large: from 5 to 9 log units. If the reported phenomena do in fact occur, they must have causes entirely different from the ones proposed by the authors. The paramagnetic nature of protein complexes is found to seriously limit their utility for engineering magnetically sensitive cells .
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a commentary on three recent reports in Nature journals
an analysis of how magnetic fields affect biological molecules and cells. It was prompted by a series of prominent reports
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taught in college
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9
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One can conveniently analyze these reports with the same back-of-the-envelope calculations
The paramagnetic nature of protein complexes is found to seriously limit their utility for engineering magnetically sensitive cells