The eukaryotic cytoskeleton appears to have evolved from ancestral precursors related to prokaryotic FtsZ and MreB. FtsZ and MreB show 40–50% sequence identity across different bacterial and archaeal species. Here I suggest that this represents the limit of divergence that is consistent with maintaining their functions for cytokinesis and cell shape. Previous analyses have noted that tubulin and actin are highly conserved across eukaryotic species, but so divergent from their prokaryotic relatives as to be hardly recognizable from sequence comparisons. One (...) suggestion for this extreme divergence of tubulin and actin is that it occurred as they evolved very different functions from FtsZ and MreB. I will present new arguments favoring this suggestion, and speculate on pathways. Moreover, the extreme conservation of tubulin and actin across eukaryotic species is not due to an intrinsic lack of variability, but is attributed to their acquisition of elaborate mechanisms for assembly dynamics and their interactions with multiple motor and binding proteins. A new structure‐based sequence alignment identifies amino acids that are conserved from FtsZ to tubulins. The highly conserved amino acids are not those forming the subunit core or protofilament interface, but those involved in binding and hydrolysis of GTP. BioEssays 29:668–677, 2007. © 2007 Wiley Periodicals, Inc. (shrink)

Unlike some other reproductions of classic texts (1) We have not used OCR(Optical Character Recognition), as this leads to bad quality books with introduced typos. (2) In books where there are images such as portraits, maps, sketches etc We have endeavoured to keep the quality of these images, so they represent accurately the original artefact. Although occasionally there may be certain imperfections with these old texts, we feel they deserve to be made available for future generations to enjoy.

An important question for bacterial cell division is how the invaginating septum can overcome the turgor force generated by the high osmolarity of the cytoplasm. I suggest that it may not need to. Several studies in Gram‐negative bacteria have shown that the periplasm is isoosmolar with the cytoplasm. Indirect evidence suggests that this is also true for Gram‐positive bacteria. In this case the invagination of the septum takes place within the uniformly high osmotic pressure environment, and does not have to (...) fight turgor pressure. A related question is how the V‐shaped constriction of Gram‐negative bacteria relates to the plate‐like septum of Gram‐positive bacteria. I collected evidence that Gram‐negative bacteria have a latent capability of forming plate‐like septa, and present a model in which septal division is the basic mechanism in both Gram‐positive and Gram‐negative bacteria. (shrink)

This is the first comprehensive study of Nietzsche's earliest (and extraordinary) book, The Birth of Tragedy (1872). When he wrote it, Nietzsche was a Greek scholar, a friend and champion of Wagner, and a philosopher in the making. His book has been very influential and widely read, but has always posed great difficulties for readers because of the particular way Nietzsche brings his ancient and modern interests together. The proper appreciation of such a work requires access to ideas that cross (...) the boundaries of conventional specialisms. This is now provided by M. S. Silk and J. P. Stern in their joint study of Nietzsche's book. They examine in detail its content, style and form; its strange genesis and hybrid status; its biographical background and the controversy engendered by its publication; its value as an account of ancient Greek culture and as a theory of tragedy and music; its relation to other theories of tragedy; and its place in the history of German ideas and in Nietzsche's own philosophical career. (shrink)

The first comprehensive study of Nietzsche's earliest book, The Birth of Tragedy, this important volume by M. S. Silk and J. P. Stern examines the work in detail: its place in Nietzsche's philosophical career; its value as an account of ancient Greek culture; its place in the history of German ideas, and its value as a theory of tragedy and music. Presented in a fresh twenty-first-century series livery, and including a specially commissioned preface written by Lesley Chamberlain, illuminating its enduring (...) importance and relevance to philosophical enquiry, this accessible study has been revived for a new generation of readers. (shrink)

Among the most striking aspects of modern literature—expecially of modern German literature—are its frequent references to a notion called ‘reality’. The philosophical question this raises, ‘What is reality?’, is to one side of this enquiry, and so is the question whether or not this is a sensible question: this essay is intended as a contribution not to philosophy but to its connections with literary history and criticism. My present purpose, which determines my procedure, is to outline the various closely related (...) meanings of the word ‘Wirklichkeit’ throughout its very long history; to describe the polarization of meanings which occurred in the course of the nineteenth century, and Nietzsche's part in making the new polarity available to his literary heirs; to illustrate the way German literature became involved in this process in the first decade of our century; and, finally, to point to some of its political implications. My argument is part of a much larger topic, one that is not confined either to the German-speaking countries or indeed to literature. The topic, the ideologizing of ‘ reality ’, is relevant to all modern cultures. The present paper offers no more than a sketch of this development in one cultural area of our world. (shrink)

Among the most striking aspects of modern literature—expecially of modern German literature—are its frequent references to a notion called ‘reality’. The philosophical question this raises, ‘What is reality?’, is to one side of this enquiry, and so is the question whether or not this is a sensible question: this essay is intended as a contribution not to philosophy but to its connections with literary history and criticism. My present purpose, which determines my procedure, is to outline the various closely related (...) meanings of the word ‘Wirklichkeit’ throughout its very long history; to describe the polarization of meanings which occurred in the course of the nineteenth century, and Nietzsche's part in making the new polarity available to his literary heirs; to illustrate the way German literature became involved in this process in the first decade of our century; and, finally, to point to some of its political implications. My argument is part of a much larger topic, one that is not confined either to the German-speaking countries or indeed to literature. The topic, the ideologizing of ‘reality’, is relevant to all modern cultures. The present paper offers no more than a sketch of this development in one cultural area of our world. (shrink)