Their starting proteins phosphorylated

During cell division, a replication-competent state is established at the replication start sites, the pre-RC. This contains the ORC, the MCM proteins and the cdc6 protein. Formation of the pre-RC in late M phase and in G1 phase licenses the chromatin for DNA replication. With entry into S phase, the MCM proteins and the Cdc6 protein dissociate from the start site. Their phosphorylation by an active S phase cyclin-CDK complex is responsible for the dissociation. 

Kinases activate a large group of lytic enzymes by phosphorylation. Lytic enzymes are localized mainly in the cytosol [133]. Their activation requires an acidic pH [134-136]. Thus proteases [137], and nucleases [138,139] are activated which start cell degradation of proteins and nucleic acids. 

Figure 1. Cellular response to DNA damage. Sensor proteins are able to detect the presence of DNA damage and alert the cellular machinery so that the cell can face the stress and protects itself. The sensor then activates a transducer and through a series of proteins activation by phosphorylations, DNA integrity checkpoints (red arrow), in charge ofthe cell cycle control are activated and play their role which is to stop the cell cycle progression In order to allow repair to fully operate. Indeed, DNA replication should not occur on damaged DNA because of possible mistakes when copying modified bases, so the G l/S interphase checkpoint prevents the cell to enter into S-phase and to start replication. The G2 checkpoint verifies DNA for the presence of double strand breaks and incomplete replication, so that an altered DNA copy is not transmitted to the daughter cell.

Starting from UDP-Glc, a variety of a-D-Gal-(l- 4)-P-D-Gal derivatives have been prepared using a UDP-Glc-4-epimerase-a-l,3-Gal-transferase fusion enzyme. The fusion protein enhanced reaction rates by 300yo compared to the same reactions carried out with equivalent amounts of the two separate en-zymes. A one-pot route to ketoses, such as 38, from glycerol and pyrophosphate, via their phosphorylated precursors 37 has been developed using phytase (Scheme 8). ... 

As long ago as 1827 W. Prout had recognised three types of complex food components, which today are known as carbohydrates, fat (lipids) and proteins. It was not until much later that another component, nucleic acids, was also recognised, and that all these four components were often present in phosphorylated forms. Only in the latter part of the nineteenth century did the beneficial effects of added (often simple) phosphorns compounds start to be appreciated. Only by the middle of the twentieth century was their mass use by the food industries firmly established. 

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