Ferent authors or the same authors in different conditions, are counted only once, the number of different motors is approximately 265 (the uncertainty SB 203580 site arises from a few measurements in table 4 which were made on a mixture of distinct fibres or several muscles together).rsos.royalsocietypublishing.org R. Soc. open sci. 3:…………………………………………2.4. Other motor classificationsThe data were also analysed with respect to the structure of motors, their function and the taxonomic position of the organisms. For comparing structures, the original 13 types, from molecules to muscles, were aggregated in five Talmapimod site classes (M1, M2, FI, MU, MV) or two classes (molecular M1 + M2 and non-molecular) as defined above. In some figures and table 5, MF, for which the cross-section was indicated in the articles cited, was shown separately from the other M2 motors. The functional groups were defined by the contribution of the motor to the overall movement of their parent organism, the four basic categories being swimming (Swim), flying (Fly), moving with respect to a solid surface (terrestrial Terr) and no direct contribution to locomotion (non-loc). Examples of non-loc motors are RNA polymerase, cytoplasmic dynein, kinesin, F0 /F1 -ATPase and various muscular motors (heart, diaphragm, wing closer, gill pump, claw closer, larynx, eye). For taxonomic comparisons, groups 5 with number of f values less than 5 (protozoa, algae, fungi, echinoderms, arachnids) were excluded.2.5. Body massFinally, the tensions were analysed with respect to the mass M of the `body’ that the motor contributes to move. For molecular motors this is the mass of the cell from which the motor was extracted. When not reported, cell masses were estimated from other sources or calculated from the cell size. In nonmolecular motors, tensions were analysed with respect to the mass M of the corresponding animal. When not reported, body masses were also estimated from other sources. Note that as a consequence of these choices a different mass was used for a myosin molecule (molecular motor) and a muscle fibre (non-molecular motor) from the same organism. The organisms considered range in mass from the bacterium Escherichia coli (1.3 ?10-15 kg) to the muscular fibre (5 ?10-8 kg) for the cells, and from the mite Archegozetes longisetosus (10-7 kg) to the elephant (2500 kg) for the multicellular organisms. For both f and M, means of a series of equivalent measurements by the same author(s) were preferred when available. When only minimum and maximum values were given, we took their mean.2.6. StatisticsStatistical distributions were compared with the Kolmogorov mirnov test [194]. Multiple distributions were compared with the one-way analysis of variance (ANOVA) and corresponding multiple comparison of means using Tukey ramer adjustment. Slopes of least-square regressions of log10 (f ) versus log10 (M) were compared with 0 using the F test. Details of statistical analyses are given as the electronic supplementary material, tables S1 6 for ANOVA and multiple comparison of means and tables S7 12 for regressions. All tests were performed with the MATLAB STATISTICAL TOOLBOX (The Mathworks, Natick, USA).3. ResultsThe data have been analysed in terms of the maximum force per cross-sectional area f. We consider separately motors made of single molecules (denoted M1) and molecular assemblies (M2, MF) that we collectively call `molecular motors’, whereas the other motors, muscle fibres (FI.Ferent authors or the same authors in different conditions, are counted only once, the number of different motors is approximately 265 (the uncertainty arises from a few measurements in table 4 which were made on a mixture of distinct fibres or several muscles together).rsos.royalsocietypublishing.org R. Soc. open sci. 3:…………………………………………2.4. Other motor classificationsThe data were also analysed with respect to the structure of motors, their function and the taxonomic position of the organisms. For comparing structures, the original 13 types, from molecules to muscles, were aggregated in five classes (M1, M2, FI, MU, MV) or two classes (molecular M1 + M2 and non-molecular) as defined above. In some figures and table 5, MF, for which the cross-section was indicated in the articles cited, was shown separately from the other M2 motors. The functional groups were defined by the contribution of the motor to the overall movement of their parent organism, the four basic categories being swimming (Swim), flying (Fly), moving with respect to a solid surface (terrestrial Terr) and no direct contribution to locomotion (non-loc). Examples of non-loc motors are RNA polymerase, cytoplasmic dynein, kinesin, F0 /F1 -ATPase and various muscular motors (heart, diaphragm, wing closer, gill pump, claw closer, larynx, eye). For taxonomic comparisons, groups 5 with number of f values less than 5 (protozoa, algae, fungi, echinoderms, arachnids) were excluded.2.5. Body massFinally, the tensions were analysed with respect to the mass M of the `body’ that the motor contributes to move. For molecular motors this is the mass of the cell from which the motor was extracted. When not reported, cell masses were estimated from other sources or calculated from the cell size. In nonmolecular motors, tensions were analysed with respect to the mass M of the corresponding animal. When not reported, body masses were also estimated from other sources. Note that as a consequence of these choices a different mass was used for a myosin molecule (molecular motor) and a muscle fibre (non-molecular motor) from the same organism. The organisms considered range in mass from the bacterium Escherichia coli (1.3 ?10-15 kg) to the muscular fibre (5 ?10-8 kg) for the cells, and from the mite Archegozetes longisetosus (10-7 kg) to the elephant (2500 kg) for the multicellular organisms. For both f and M, means of a series of equivalent measurements by the same author(s) were preferred when available. When only minimum and maximum values were given, we took their mean.2.6. StatisticsStatistical distributions were compared with the Kolmogorov mirnov test [194]. Multiple distributions were compared with the one-way analysis of variance (ANOVA) and corresponding multiple comparison of means using Tukey ramer adjustment. Slopes of least-square regressions of log10 (f ) versus log10 (M) were compared with 0 using the F test. Details of statistical analyses are given as the electronic supplementary material, tables S1 6 for ANOVA and multiple comparison of means and tables S7 12 for regressions. All tests were performed with the MATLAB STATISTICAL TOOLBOX (The Mathworks, Natick, USA).3. ResultsThe data have been analysed in terms of the maximum force per cross-sectional area f. We consider separately motors made of single molecules (denoted M1) and molecular assemblies (M2, MF) that we collectively call `molecular motors’, whereas the other motors, muscle fibres (FI.
