Biology subjects

Liao, X.-P.

Publications and source records attributed to Liao, X.-P..

3 recordsLinked to original sources

bioRxiv2023

Synergistic efficacy of tigecycline combined with apramycin against tet(X)-harboring Acinetobacter spp.

The emergence of the wide variety of novel tigecycline resistance tet(X) variants including tet(X3), tet(X4), tet(X5) and tet(X6) has posed a significant challenge to the clinical treatment of multidrug-resistant bacterial infections and represents a serious threat to global public health. The purpose of this study was to evaluate the synergism of tigecycline combined with other antibiotics as a means of overcoming tet(X)-mediated resistance in Acinetobacter spp. We found that the combinations of tigecycline with apramycin or amikacin exhibited synergistic activity against tet(X)-harboring Acinetobacter spp. with FICI values of 0.088 and 0.625, respectively. The MICTGC decreased >5-fold decrease in the presence of subinhibitory levels of apramycin. This combination was shown to be a therapeutically effective synergism using both in vitro and in vivo (mouse thigh infection model) assays and delayed the increase of MIC values over time. This study highlights the synergism of tigecycline in combination with apramycin which offers a viable therapeutic alternative for infections caused by tet(X)-harboring Acinetobacter.

pharmacology and toxicology↗

bioRxiv2021

Source tracking and global distribution of the mobilized tigecycline resistant gene tet(X)

The emergence of tet(X) genes has compromised the clinical use of the last-line antibiotic tigecycline. We identified 322 (1.21%) tet(X) positive samples from 12,829 human microbiome samples distributed in four continents (Asia, Europe, North America and South America) using retrospective data from worldwide. These tet(X) genes were dominated by tet(X2)-like orthologs but we also identified 12 samples carrying novel tet(X) genes, designed tet(X15) and tet(X16), that were resistant to tigecycline. The metagenomic analysis revealed these tet(X) genes distributed in anaerobes dominated by Bacteroidaceae (78.89%) of human-gut origin. The transmission of these tet(X2)-like orthologs between Bacteroidaceae and Riemerella anatipestifer was primarily promoted by the mobile elements ISBf11 and IS4351. tet(X2)-like orthologs was also developed during transmission by mutation to high-level tigecycline resistant determinants tet(X15) and tet(X16). Further tracing these tet(X) in single bacterial isolate from public repository indicated that tet(X) genes were present as early as 1960s in R. anatipestifer that was the primary tet(X) carrier at early stage (before 2000). The tet(X2) and non-tet(X2) orthologs were primarily distributed in humans and food animals respectively, and non-tet(X2) were dominated by tet(X3) and tet(X4). Genomic comparison indicated these tet(X) genes were likely to be generated during tet(X) transmission between Flavobacteriaceae and E. coli/Acinetobacter spp.., and ISCR2 played a key role in the transmission. These results suggest R. anatipestifer was the potential ancestral source of tet(X) gene. Additionally, Bacteroidaceae of human-gut origin was an important hidden reservoir and mutational incubator for the mobile tet(X) genes that enabled spread to facultative anaerobes and aerobes.

bioinformatics↗

bioRxiv2019

Universal and naked-eye gene detection platform based on CRISPR/Cas12a/13a system

Colorimetric gene detection based on gold nanoparticles (AuNPs) is an attractive detection format due to its simplicity. Here, we report a new design for a colorimetric gene-sensing platform based on the CRISPR/Cas system that has improved specificity, sensitivity, and universality. CRISPR/Cas12a and CRISPR/Cas13a have two distinct catalytic activities and are used for specific target gene recognition. Programmable recognition of DNA by Cas12a/crRNA and RNA by Cas13a/crRNA with a complementary sequence activates the nonspecific trans-ssDNA or -RNA cleavage, respectively, thus degrading the ssDNA or RNA linkers which are designed as a hybridization template for the AuNP-DNA probe pair. Target-induced trans -ssDNA or RNA cleavage leads to a distance-dependent color change for the AuNP-DNA probe pair. In this platform, naked eye detection of transgenic rice, African swine fever virus (ASFV), and a miRNA can be completed within 1 hour. Our colorimetric gene-sensing method shows superior characteristics, such as probe universality, isothermal reaction conditions, on-site detection capability, and sensitivity that is comparable to that of the fluorescent detection; thus, this method represents a robust next generation gene detection platform.

bioengineering↗