BACKGROUND: The gut microbiome is integral to host health, hosting complex interactions between the host and numerous microbial species in the gastrointestinal tract. Key among the molecular mechanisms employed by gut bacteria are transportomes, consisting of diverse transport proteins crucial for bacterial adaptation to the dynamic, nutrient-rich environment of the mammalian gut. These transportomes facilitate the movement of a wide array of molecules, impacting both the host and the microbial community. SUMMARY: This communication explores the significance of transportomes in gut bacteria, focusing on their role in nutrient acquisition, competitive interactions among microbes, and potential pathogenicity. It delves into the transportomes of key gut bacterial species like E. coli, Salmonella, Bacteroides, Lactobacillus, Clostridia, and Bifidobacterium, examining the functions of predicted transport proteins. The overview synthesizes recent research efforts, highlighting how these transportomes influence host-microbe interactions and contribute to the microbial ecology of the gut. KEY MESSAGES: Transportomes are vital for the survival and adaptation of bacteria in the gut, enabling the import and export of various nutrients and molecules. The complex interplay of transport proteins not only supports bacterial growth and competition but also has implications for host health, potentially contributing to pathogenic processes. Understanding the pathogenic potential of transportomes in major gut bacterial species provides insights into gut health and disease, offering avenues for future research and therapeutic strategies.

• Keywords
• Disease, Health, Microbiome, Pathogenicity factors, Transport proteins, Transportome,
• MeSH
• Bacteria * metabolism   pathogenicity   MeSH
• Bacterial Proteins metabolism   MeSH
• Biological Transport MeSH
• Gastrointestinal Tract microbiology   MeSH
• Host Microbial Interactions physiology   MeSH
• Humans MeSH
• Gastrointestinal Microbiome * physiology   MeSH
• Carrier Proteins metabolism   MeSH
• Animals MeSH
• Check Tag
• Humans MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Review MeSH
• Names of Substances
• Bacterial Proteins MeSH
• Carrier Proteins MeSH

Every cell is protected by a semipermeable membrane. Peptides with the right properties, for example Antimicrobial peptides (AMPs), can disrupt this protective barrier by formation of leaky pores. Unfortunately, matching peptide properties with their ability to selectively form pores in bacterial membranes remains elusive. In particular, the proline/glycine kink in helical peptides was reported to both increase and decrease antimicrobial activity. We used computer simulations and fluorescence experiments to show that a kink in helices affects the formation of membrane pores by stabilizing toroidal pores but disrupting barrel-stave pores. The position of the proline/glycine kink in the sequence further controls the specific structure of toroidal pore. Moreover, we demonstrate that two helical peptides can form a kink-like connection with similar behavior as one long helical peptide with a kink. The provided molecular-level insight can be utilized for design and modification of pore-forming antibacterial peptides or toxins.

• Keywords
• antibiotics, fluorescent probes, membrane structure, membrane transport, molecular biophysics, none, structural biology,
• MeSH
• Models, Biological MeSH
• Cell Membrane chemistry   metabolism   MeSH
• Hydrophobic and Hydrophilic Interactions MeSH
• Antimicrobial Cationic Peptides chemistry   metabolism   MeSH
• Protein Conformation * MeSH
• Monte Carlo Method MeSH
• Models, Molecular MeSH
• Porins chemistry   metabolism   MeSH
• Structure-Activity Relationship MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Names of Substances
• Antimicrobial Cationic Peptides MeSH
• Porins MeSH