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The paper presents the work done during the two editions of the Summer School that took place in Lampedusa in 2017 and 2018, organized by the Italian Association of Sociology – Environment and Territory Section. The aim of the paper is twofold. Firstly, it aims to illustrate the results of the data analysis and field observation carried out by the participants of the School. They consist of a multi-faceted description of the Island, with special attention to its different populations (residents, city users and especially migrants), and of some resulting project proposals. Secondly, the essay aims to promote a practice based on study and training, which is typical of the sociological analysis of territory, and that can provide useful insight on the studied places and to the people of Lampedusa, within a broader vision of justice and social sustainability.

The initial steps in the biosynthesis of the tetrapyrrolic dyes, called the 'pigments of life', are highly convergent. The formation of porphobilinogen, the pyrrolic precursor of the tetrapyrrolic skeleton, uses ?-aminolevulinate as the starting material. This amino acid is dedicated to the biosynthesis of tetrapyrroles. However, the chemical condensation of ?-aminolevulinate leads to a symmetric pyrazine. Attempts to imitate the biosynthesis using one of the proposed pathways for the biosynthesis of porphobilinogen as a guideline has allowed us to synthesize a protected precursor of porphobilinogen in an efficient way. Based on the two major proposals for the biosynthesis, a series of specifically synthesized inhibitors was also tested. The inhibition behavior and the potency of the inhibitors expressed as their Ki value has unraveled an interesting relationship between the structure of the inhibitor and the strength of its interaction with the active site. The concerted use of mechanistic analysis, synthesis and kinetic studies of inhibitors has increased our knowledge about the enzyme porphobilinogen synthase. Structural studies of enzyme-inhibitor complexes will hopefully complement the kinetic results accumulated so far.