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Xingrui Li

Publications and source records attributed to Xingrui Li.

2 recordsLinked to original sources

Transferable IncHI2-Associated blaLAP-2 and blaCTX-M-55 Resistance Platforms in Foodborne Salmonella.

Extended-spectrum β-lactamase genes in foodborne Salmonella enterica can disseminate through mobile multidrug-resistance platforms. IncHI2 plasmids are important resistance vehicles capable of carrying complex resistance regions and facilitating their horizontal transfer across diverse bacterial backgrounds, but the transfer and genomic organization of IncHI2 elements co-carrying blaLAP-2 and blaCTX-M-55 remain insufficiently characterized. This study investigated two multidrug-resistant foodborne isolates recovered in Shanghai in 2022: Salmonella Agona ST13 isolate Sal22C150 and Salmonella Havana ST1527 isolate Sal22P208. Antimicrobial susceptibility testing, whole-genome sequencing, conjugation, plasmid-retention analysis, comparative genomics, as well as strain- and plasmid-level phylogenetic analyses were performed. Both isolates exhibited broad antimicrobial resistance, including resistance to extended-spectrum cephalosporins. In both isolates, blaLAP-2 and blaCTX-M-55 co-transferred with the IncHI2 replicon to Escherichia coli J53 at frequencies of (4.95 ± 0.41) × 10-5 and (4.46 ± 0.42) × 10-6 transconjugants per donor cell, respectively. All tested plasmid markers remained detectable through 20 passages without antimicrobial selection. Complete assembly of Sal22P208 confirmed the location of the three β-lactamase genes on the 275,096 bp IncHI2 plasmid pSal22P208. The plasmid contained a conserved conjugative backbone and mosaic accessory regions carrying 15 antimicrobial-resistance determinants together with mercury- and tellurium-resistance loci. SNP-based analysis placed pSal22P208 within a closely related cluster containing six reference IncHI2 plasmids differing by fewer than 30 SNPs and recovered from Salmonella and E. coli of animal, food, and human origin, suggesting a broad distribution of this plasmid lineage across diverse bacterial and ecological backgrounds. Sal22P208 additionally contained a Tn3-associated chromosomal multidrug-resistance region between rpmJ and rpmE that shared extensive structural similarity with a region in Citrobacter braakii LBA3. These findings highlight the role of transferable IncHI2 resistance platforms in the horizontal dissemination and short-term post-transfer maintenance of linked resistance determinants, while chromosomally integrated resistance regions may provide an additional route for the accumulation and inheritance of multidrug resistance in foodborne Salmonella.

IncHI2 plasmid

AI-driven CRISPR screening: optimizing gene editing through automation and intelligent decision support.

BACKGROUND: CRISPR-based genetic screening has become a central methodology in functional genomics, enabling systematic interrogation of gene function, genetic interactions and context-dependent vulnerabilities at scale. However, the rapid expansion of screening modalities-including multi-condition designs, combinatorial perturbations, in vivo applications and single-cell readouts-has exposed fundamental limitations of heuristic-driven experimental design and post hoc statistical analysis. MAIN BODY: This Review synthesizes how artificial intelligence is reshaping CRISPR screening by introducing predictive, adaptive and system-level intelligence across the experimental lifecycle. We organize recent advances into two tightly coupled modules. First, machine learning and deep learning (ML/DL) methods optimize experimental design by learning context-dependent perturbation behavior, anticipating confounding effects and enabling iterative, information-efficient screening strategies. Second, large language model-agent (LLM-agent) systems complement these advances by externalizing scientific reasoning, integrating biological knowledge at scale and coordinating analysis and decision-making in human-in-the-loop workflows. CONCLUSIONS: Together, ML/DL and LLM-agent approaches reframe CRISPR screening from a static analytical pipeline into an intelligent experimental system, with important implications for robustness, scalability and biological discovery.

Artificial Intelligence