Carbapenem resistance's global proliferation poses a significant public health challenge. The primary resistance mechanism is carbapenemase production. In this study, we discovered a novel carbapenemase, RATA, located on the chromosome of Riemerella anatipestifer isolates. This enzyme shares ≤52 % amino acid sequence identity with other known β-lactamases. Antimicrobial susceptibility tests and kinetic assays demonstrated that RATA could hydrolyze not only penicillins and extended-spectrum cephalosporins but also monobactams, cephamycins, and carbapenems. Furthermore, its activity was readily inhibited by β-lactamase inhibitors. Bioinformatics analysis revealed 46 bla RATA -like genes encoding 27 variants in the NCBI database, involving 21 different species, including pathogens, host-associated bacteria, and environmental isolates. Notably, bla RATA -positive strains were globally distributed and primarily collected from marine environments. Concurrently, taxonomic analysis and GC content analysis indicated that bla RATA orthologue genes were predominantly located on the chromosomes of Flavobacteriaceae and shared a similar GC content as Flavobacteriaceae . Although no explicit mobile genetic elements were identified by genetic environment analysis, bla RATA-2 possessed the ability of horizontal transfer in R. anatipestifer via natural transformation. This work's data suggest that RATA is a new chromosome-encoded class A carbapenemase, and Flavobacteriaceae from marine environments could be the primary reservoir of the bla RATA gene.
Yue Wang,Jianing Li,Tingting Zhu,Yiran Li,Jinyu Yang,Tingting Ma,Yulin Fang,Xiangyu Sun
Sub-regional characteristic differentiation is crucial for development of wine regions, particularly for emerging regions. This study aims to identify and quantify the key aroma-active compounds and to analyze the aroma characteristics in Marselan wines from different Ningxia sub-regions using sensomics methods and the rate-all-that-apply approach. By employing GC × GC-qTOFMS and GC-O, we comparatively evaluated the contributions of the aroma-active compounds from four sub-regions. Fifty-three aroma-active compounds were identified. Seven compounds were important contributors to the fruity aroma. The omission experiments further confirmed the important contribution of ethyl hexanoate and β -damascenone to the floral and fruity characters. Yinchuan was characterized by its floral and fruity notes and methyl octanoate and ethyl octanoate were the main contributors. Qingtongxia and Yongning were characterized by Sweet spice , driven by nonanal and 4-methyl-1-pentanol. The differences in aroma profiles and the chemical basis across the sub-regions of Ningxia provide compelling evidence reinforcing the intra-regional micro- terroir.
Yuan Xu,Yan Ping Chen,Shaolin Deng,Chunbao Li,Xinglian Xu,Guanghong Zhou,Yuan Liu
Blanched chicken, boiling the whole chicken without removing head and butt parts during process, is a traditional poultry product in China. In this manuscript, the flavor differences of five parts (skin, breast, thigh, head and butt) of the Chinese blanched chicken (CBC) were studied using sensory evaluation and instrumental analysis. Check-all-that-apply (CATA), rate-all-that-apply (RATA), and 9-point hedonic preference were used to collect consumers’ sensory results. Gas chromatograph-time of flight mass spectrometer (GC-ToF-MS) and electronic nose (E-nose) were used to discriminate flavor variances. CATA perceptions showed different parts of CBC stimulated consumers’ odor and emotion feelings differently. GC-ToF-MS and E-nose data elaborated that the flavor of breast with chicken-like flavor was better than the other parts. Consumers preferred the chicken breast part the most. This analysis of different parts of CBC could provide advice to cater consumers’ preference and predict the quality change might induce.
危险品化学品经营许可证（带存储）