Bromodomain (BRD) proteins exhibit a variety of activities, such as histone modification, transcription factor recruitment, chromatin remodeling, and mediator or enhancer complex assembly, that affect transcription initiation and elongation. These proteins also participate in epigenetic regulation. Although specific epigenetic regulation plays an important role in the occurrence and development of cancer, the characteristics of the BRD family in renal clear cell carcinoma (KIRC) have not been determined. In this study, we investigated the expression of BRD family genes in KIRC at the transcriptome level and examined the relationship of the expression of these genes with patient overall survival. mRNA levels of tumor tissues and adjacent tissues were extracted from The Cancer Genome Atlas (TCGA) database. Seven BRD genes (KAT2A, KAT2B, SP140, BRD9, BRPF3, SMARCA2, and EP300) were searched by using LASSO Cox regression and the model with prognostic risk integration. The patients were divided into two groups: high risk and low risk. The combined analysis of these seven BRD genes showed a significant association with the high-risk groups and lower overall survival (OS). This analysis demonstrated that total survival could be predicted well in the low-risk group according to the time-dependent receiver operating characteristic (ROC) curve. The prognosis was determined to be consistent with that obtained using an independent dataset from TCGA. The relevant biological functions were identified using Gene Set Enrichment Analysis (GSEA). In summary, this study provides an optimized survival prediction model and promising data resources for further research investigating the role of the expression of BRD genes in KIRC.

Florfenicol is widely used to control respiratory diseases and intestinal infections in food animals. However, there are increasing reports about florfenicol resistance of various clinical pathogens. floR is a key resistance gene that mediates resistance to florfenicol and could spread among different bacteria. Here, we investigated the prevalence of floR in 430 Pseudomonas aeruginosa isolates from human clinical samples and identified three types of floR genes (designated floR, floR-T1 and floR-T2) in these isolates, with floR-T1 the most prevalent (5.3%, 23/430). FloR-T2 was a novel floR variant identified in this study, and exhibited less identity with other FloR proteins than FloRv. Moreover, floR-T1 and floR-T2 identified in P. aeruginosa strain TL1285 were functionally active and located on multi-drug resistance region of a novel incomplete Tn4371-like integrative and conjugative elements (ICE) in the chromosome. The expression of the two floR variants could be induced by florfenicol or chloramphenicol. These results indicated that the two floR variants played an essential role in the host’s resistance to amphenicol and the spreading of these floR variants might be related with the Tn4371 family ICE.

In this study, we characterized a novel chromosome-encoded aminoglycoside nucleotidyltransferase (ANT), AadA36, from the Providencia stuartii strain P14 isolated from the sputum specimen of a burn patient at a hospital in Wenzhou, China. Among the functionally characterized ANTs, AadA36 shared the highest amino acid sequence identity of 51.91% with AadA14. The whole genome of P. stuartii P14 consisted of one chromosome and two plasmids (designated pP14-166 and pP14-114). A total of 19 genes with ≥80% similarity with functionally characterized antimicrobial resistance genes (ARGs) were identified in the whole genome, including aminoglycosides [aac(2′)-Ia, aph(6)-Id, aph(3″)-Ib, aac(6′)-Ib, ant(3″)-IIa, aph(3′)-Ia], β-lactams (blaCMY-2 and blaOXA-10) and so on. Antimicrobial susceptibility testing showed that the aadA36 gene conferred specific resistance to spectinomycin and streptomycin, and the minimum inhibitory concentration (MIC) of these antimicrobials increased 128- and 64-fold compared with the control strain. The kinetic parameters of AadA36 were consistent with the MIC data of spectinomycin and streptomycin, with kcat/Km ratios of (1.07 ± 2.23) × 104 M−1 s−1 and (8.96 ± 1.01) × 103 M−1 s−1, respectively. The identification of a novel aminoglycoside resistance gene will help us further understand the complexity of the resistance mechanisms and provide deep insights into the dissemination of resistance genes in the microbial population.