Introduction: Personal Interludes (original) (raw)

In the early spring of 1980, one of the authors of this book (E.V.K.) was an excited listener to a seminar presented in Moscow State University, the authors’ alma mater, by a well-known virologist, a scientist of rare creativity, and later a good friend, Anatoly Altstein. The subject of the seminar was a model of the origin of the genetic coding and translation he had developed [23]. The model was a beauty, but it was hard to imagine how one would go about verifying it (just in case the reader is curious, an attempt to test this idea using actual molecular models of nucleotides and amino acids has been subsequently published [24]). Toward the end of the seminar, upon answering the question about validation of the model for the umpteenth time, Anatoly dropped, rather casually, something to the effect of “Not to worry, we will soon have many gene sequences to compare and will be able to reconstruct the earliest stages of evolution”. This was the first occasion for the author, at the time a struggling graduate student in virology with a persistent but futile interest in evolution, to grasp the idea of comparative genomics. Even so, he remained skeptical as to the potential of sequence comparison to solve the mystery of the Origin of Life. Little did he know that his entire career in science would be dedicated to this very objective: understanding evolution through comparisons of genes, genomes, and proteins. Now, 22 years after that memorable seminar, we are still far from understanding the origin of coding. Perhaps this is the “singularity” of biological evolution that cannot be reached through reconstruction based on the comparative method. However, comparative genomics has already revealed many fascinating aspects of all subsequent stages of evolution and is bringing us breathtakingly close to the Beginning.

At about the same time and in the same building, the other author (MYG), then a graduate student in membrane biochemistry, learned about the similarity of membrane organization and energy-transducing processes in bacteria, mitochondria, and chloroplasts. He became interested in the apparent paradox: if survival of any living cells depends on the integrity of its cytoplasmic membrane that maintains the electric charge and transmembrane gradients of Na and K ions, such a system could not have evolved in steps—a membrane that is freely permeable (or entirely impermeable) is not functional. The interest in the origin and evolution of membrane energy-coupling mechanisms has finally brought this author to—where else?—comparative genomics of microorganisms. Although the principal questions in membrane evolution still remain unresolved, we are gradually approaching a better understanding of the Beginning of Life in that respect, too.