About the Authors

Andrew E Greenstein

Affiliation Department of Molecular and Cell Biology, University of California, Berkeley, California, United States of America

Jason A MacGurn

Affiliation Department of Microbiology and Immunology, University of California San Francisco, San Francisco, California, United States of America

Christina E Baer

Affiliation Biophysics Graduate Group, University of California, Berkeley, California, United States of America

Arnold M Falick

Affiliation Howard Hughes Medical Institute Mass Spectrometry Laboratory, University of California, Berkeley, California, United States of America

Jeffery S Cox

Affiliation Department of Microbiology and Immunology, University of California San Francisco, San Francisco, California, United States of America

Tom Alber

To whom correspondence should be addressed. E-mail: tom@ucxray.berkeley.edu

Affiliation Department of Molecular and Cell Biology, University of California, Berkeley, California, United States of America

Competing Interests

The authors have declared that no competing interests exist.

Author Contributions

AEG, JAM, JSC, and TA conceived and designed the experiments. AEG, JAM, CEB, and AMF performed the experiments. AEG, JAM, AMF, JSC, and TA analyzed the data. AEG, JAM, and AMF contributed reagents/materials/analysis tools. AEG, JAM, CEB, AMF, JSC, and TA wrote the paper.