The unique family of membrane‐bound proton‐pumping inorganic pyrophosphatases, involving pyrophosphate as the alternative to ATP, was investigated by characterizing 166 members of the UniProtKB/Swiss‐Prot + UniProtKB/TrEMBL databases and available completed genomes, using sequence comparisons and a hidden Markov model based upon a conserved 57‐residue region in the loop between transmembrane segments 5 and 6. The hidden Markov model was also used to search the approximately one million sequences recently reported from a large‐scale sequencing project of organisms in the Sargasso Sea, resulting in additional 164 partial pyrophosphatase sequences. The strongly conserved 57‐residue region was found to contain two nonapeptidyl sequences, mainly consisting of the four ‘very early’ proteinaceous amino acid residues Gly, Ala, Val and Asp, compatible with an ancient origin of the inorganic pyrophosphatases. The nonapeptide patterns have charged amino acid residues at positions 1, 5 and 9, are apparent binding sites for the substrate and parts of the active site, and were shown to be so specific for these enzymes that they can be used for functional assignments of unannotated genomes.
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AbstractBetween 2001 and 2009, the area of Naples, South Italy, repeatedly hit the headlines of national and international media due to the waste management crisis that on many occasions filled up the streets of the region with huge piles of waste. What soon emerged as the main bone of contention concerned the connections between the population's health and the presence of dumps on the territory. What the risks for health actually were, who was entitled to assess them, and whether pollution from proximity to dumps caused health problems were all topics that came to the fore during a debate that took place within the Italian epidemiological community, alongside the political and governance crisis.
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