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Overuse of sulfonamides in aquaculture and agriculture leads to residual drugs that cause serious pollution of the environment. However, the residues of sulfonamides in the environment are not unique, and the existing microbial degradation technology has a relatively low degradation rate of sulfonamides. Therefore, in this study, a Pseudomonas stutzeri strain (DLY-21) with the ability to degrade four common SAs was screened and isolated from aerobic compost. Under optimal conditions, the DLY-21 strain degraded four sulfonamides simultaneously within 48 h, and the degradation rates were all over 90%, with the average degradation rates of SAs being sulfoxide (SDM) ≈ sulfachloropyridazine (SCP) > sulfa quinoxaline (SQ) > sulfadiazine (SQ). In addition, the main compounds of the strain DLY-21-degrading SAs were identified by LC-MS analysis. On this basis, four detailed reaction pathways for SA degradation were deduced. This is the first report of the use of a P. stutzeri strain to degrade four sulfonamide antibiotics (SQ, SDM, SCP, and SM1), which can improve the removal efficiency of sulfonamide antibiotic pollutants and thus ameliorate environmental pollution. The results showed that DLY-21 had a good degradation effect on four SAs (SQ, SDM, SCP, and SM1).

【Objective】With the rapid development of large-scale livestock and poultry breeding industry, the pollution of sulfonamide antibiotics in livestock and poultry manure is becoming more and more prominent. The study aims to evaluate the migration and transformation characteristics of sulfonamide antibiotics in livestock manure in soil-plant-water system.【Method】The corn plants were planted in the soil without fertilizer, compound fertilizer, chicken manure and pig manure, and the concentrations of sulfonamide antibiotics in soil, leachate and plants at different growth periods of corn were determined by rotary evaporator and high performance liquid chromatograph(HPLC), then the adsorption or desorption characteristics and migration ability of sulfonamide antibiotics in livestock manure-soil system were studied.【Result】Most(67.65% and 42.74%)of sulfonamide antibiotics in the soil where chicken manure and pig manure were applied decomposed naturally, while the undecomposed sulfonamide antibiotics migrated to the deep soil layer(12.59% and 28.59%), and only a small amount (0.66% and 1.66%)of the antibiotics migrated to the soil leachate. The root was the main accumulation part of sulfonamide antibiotics, and no sulfonamide antibiotics were detected in corn fruit.【Conclusion】Sulfonamide antibiotics in livestock manure will accumulate in plants through soil, and root is the main accumulation part, therefore, root crops may be more susceptible to sulfonamide antibiotic pollution.

The resistance of synovial sublining macrophages to apoptosis has a crucial role in joint inflammation and destruction in rheumatoid arthritis (RA). However, the underlying mechanism is incompletely understood. Here we report that inactivation of the pro-apoptotic BCL-2 family protein BAD is essential for survival of synovial sublining macrophage in RA. Genetic disruption of Bad leads to more severe joint inflammation and cartilage and bone damage with reduced apoptosis of synovial sublining macrophages in collagen-induced arthritis (CIA) and TNFα transgenic (TNF-Tg) mouse models. Conversely, Bad3SA/3SA mice, in which BAD can no longer be inactivated by phosphorylation, are protected from collagen-induced arthritis. Mechanistically, phosphorylation-mediated inactivation of BAD specifically protects synovial sublining macrophages from apoptosis in highly inflammatory environment of arthritic joints in CIA and TNF-Tg mice, and in patients with RA, thereby contributing to RA pathology. Our findings put forward a model in which inactivation of BAD confers the apoptosis resistance on synovial sublining macrophages, thereby contributing to the development of arthritis, suggesting that BAD may be a potential therapeutic target for RA.