DNA Replication in Bacteria With 6 Figures

摘要: Experiments by Cairns (1963), Meselson and Stahl (1958) others (see review Bonhoeffer Messer, 1969) have shown that replication of DNA proceeds sequentially, daughter strands opposite polarity being synthesised concurrently as a fork advances along replicating molecule. On the other hand bacterial polymerase characterised Kornberg his collaborators (Kornberg, well those found in phage-infected cells tissues higher organisms, all appear to utilise 5′ deoxynucleoside triphosphates precursors proceed chain elongation 5′-to-3′ direction only (Richardson, 1969). What then is mechanism which strand runs 3′-to-5′ with respect overall ? One possibility its synthesis involves reaction 3-OH triphosphate 5′-triphosphate group terminating growing chain, or 3′-triphosphates 5-OH terminus (Mitra Kornberg, 1966) (Fig. 1 A). However there no evidence either type can be catalysed any known enzymes, including recently discovered II section III),