Cross-contamination is a major food safety risk during the harvesting and processing of fresh produce, leading to significant losses in global human well-being and the economy. The surface of food contact areas is a high-risk zone for cross-contamination. Therefore, developing an effective antimicrobial coating for food-contact surfaces is essential. This study developed a smart antimicrobial coating that self-regulated in response to environmental conditions, via grafting the stimuli-responsive polymer polyacrylic acid (PAA) and the phage-derived endolysin Lysin81 onto ZnO nanocolumns. During the initial stage of bacterial adhesion, the surface of the nanocolumns exhibited significant mechanical bactericidal activity, while the super hydrophilic PAA layer effectively inhibited bacterial adhesion. At a later stage, when numerous live and dead bacteria adhered to the surface of the nanocolumns, the PAA chains disintegrated, exposing the underlying layer of endolysin that lysed the compromised bacteria. In addition, as the environmental pH increases, the attached dead bacteria can be released once the PAA chains regain their hydrophilicity. This research aimed to apply the antibacterial coating to stainless steel surfaces used in food processing, potentially enhancing surface hygiene and preventing cross-contamination of fresh produce.
The human gut microbiome contains numerous proteins whose functions remain elusive yet are pivotal to host health. Sequence-based methods often falter when attempting to infer functions within this microbial proteome due to evolutionary divergence. To address this challenge, we develop the Human Gut Microbial Protein Structure Database, which incorporates ∼2.7 million predicted protein structures. Our findings reveal that structural analogy enhances the annotation of phage proteins. We detail the structural diversification of phage endolysins and confirm their potential in eliminating gut pathobionts. Furthermore, our structure-guided approach is effective in the identification of microbial-host isozymes. By employing structural alignments, we identify previously unrecognized bacterial enzymes involved in melatonin biosynthesis. Finally, we present an alignment-free method, dense enzyme retrieval, based on structure-encoded protein language models for ultrafast and sensitive detection of remote homologs. Our research underscores the value of computational structural genomics in elucidating the functional landscape of the human gut microbiome.
危险品化学品经营许可证（带存储）