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Dear Colleagues,

Gram-negative bacteria have been classified from the WHO as the most critical priorities for the search of new anti-infectives. The pharmacological targets in Gram-negative bacteria are difficult to address. Though modern sequencing techniques have given access to innumerable potential new targets, the molecules identified with high-throughput screening campaigns are not able to be effective against bacteria in vivo. The singularity of Gram-negative species is a complex cell wall composed by an additional tick outer membrane with asymmetric composition. The outer membrane and its constituents (porins, specific transporters, and efflux pumps) are able to modulate the transport of molecules in and out, representing a complex filtering system for any molecule. Understanding the permeation of molecules in Gram-negative bacteria and their internal accumulation represents a scientific challenge for modern science and a boost to revitalize the early drug discovery phase. This Special Issue seeks manuscript submissions that further our understanding of molecular transport and eventually accumulation in Gram-negative species, in terms of structures involved an their mechanism of functioning, as well as with methods to measure accumulations and predictive tools

Dr. Matteo Ceccarelli
Guest Editor

• Keywords
• bacterial porins
• active transporters
• siderophores
• efflux pumps
• outer membrane
• accumulation
• permeation
• kinetics
• predictive models