One of the technical bottlenecks limiting the high yield of 1,4-butanediamine is the insufficient tolerance of strains to 1,4-butanediamine. Enhancing the tolerance of strains to 1,4-butanediamine is therefore a primary challenge that needs to be addressed for the construction of strains with high yields of 1,4-butanediamine. Staphylococcus pasteuri 326180 exhibits exceptional tolerance to high-concentration 1,4-butanediamine, serving as both an ideal model for studying the mechanism underlying the 1,4-butanediamine tolerance and a novel host for constructing strains capable of efficiently producing 1,4-butanediamine. However, for both the research on the tolerance mechanism and the modification of chassis strains, gene editing of S. pasteuri needs to be carried out at the molecular level. The research objective of this paper is to establish a genetic manipulation system for S. pasteuri, laying foundation for subsequent studies on tolerance mechanism and the modification of chassis strains. This study systematically optimized the electroporation conditions, including key parameters such as the growth phase of cells, electric field strength, electroporation buffer, and recovery medium, successfully establishing an electroporation method for S. pasteuri. Additionally, we constructed the gene editing plasmid pCpfOA by replacing the resistance expression cassette, optimized the selection markers for gene editing, and finally established a CRISPR/Cpf1-based gene editing technology for S. pasteuri, achieving an editing efficiency of 90%. The genetic manipulation system of S. pasteuri established in this study provides technical support for research into the tolerance mechanism of this bacterium and the genetic modification of chassis strains.
Staphylococcus/drug effects* ; Gene Editing/methods* ; Electroporation/methods* ; Plasmids/genetics* ; CRISPR-Cas Systems ; Genetic Engineering/methods*

Objective To investigate the anticoagulation status of patients with atrial fibrillation(AF)-related acute ischemic stroke(AIS)after revascularization therapy in the real world.Methods A retrospective study was performed on patients diagnosed as AIS and AF from Jan.2019 to Jan.2022 at The Second Affiliated Hospital of Nanchang University.Patients treated with intravenous thrombolysis(IVT),endovascular thrombectomy(EVT),or both were enrolled.Clinical information,timing of anticoagulation initiation,treatment regimens,and outcomes were documented and statistically analyzed.Additionally,a questionnaire was administered to the primary physicians to understand reasons for delaying or not initiating anticoagulation.Results A total of 189 patients with AF-related AIS met the screening criteria,including 86(45.5%)cases in the IVT group,63(33.3%)cases in the EVT group,and 40(21.2%)cases in the IVT+EVT group.The mean age of 189 patients was(72.90±9.23)years old.There were 93(49.2%)female patients.Anticoagulation was initiated within 14 d after revascularization therapy in 36.0%(68/189)of patients,with the highest rate in the IVT group(58.8%,40/68),followed by the EVT group(22.1%,15/68)and IVT+EVT group(19.1%,13/68).A significant difference was found in the proportion of patients receiving anticoagulation within 14 d among the 3 groups(P=0.020).Univariate analysis was performed on the clinical data of patients who initiated anticoagulation within 14 d after revascularization therapy(68 cases)and those who delayed or did not initiate anticoagulation(121 cases).The results showed that there were significant differences in the stroke history,National Institutes of Health stroke scale(NIHSS)score before revascularization therapy,Alberta Stroke Program early computed tomography score,modified Rankin scale(mRs)score before revascularization therapy,imaging characteristics(lesions near cortex,large infarction,severe stenosis or occlusion of major intracranial arteries),revascularization therapy method,NIHSS score 3 d after revascularization therapy,and intracranial hemorrhagic transformation after revascularization therapy between the 2 groups(all P＜0.05).Multivariate logistic regression analysis indicated that higher NIHSS scores 3 d after revascularization therapy(odds ratio[OR]=1.113,95%confidence interval[CI]1.053-1.176,P＜0.001)and the presence of intracranial hemorrhage after revascularization therapy(OR=6.098,95%CI 2.004-18.193,P=0.001)were significant factors that contraindicated the initiation of anticoagulation.Large infarcts(40.8%),infarct location(35.8%),and hemorrhagic transformation after stroke(40.8%)were the common reasons cited by physicians for not initiating anticoagulation.In the 90-d prognosis of patients with AF-related AIS,6 patients had bleeding events,and 116 patients had a good prognosis(mRS score of 0-2).The 90-d good prognosis rate in the initiated anticoagulation group within 14 d after revascularization therapy(89.7%,61/68)was significantly higher than that in the delayed or non-anticoagulation group(45.5%,55/121;P＜0.001).Conclusion For patients with AF-related AIS who receive IVT,EVT or IVT+EVT,it is safe to initiate anticoagulation early after revascularization therapy,but the timing of anticoagulation in most patients is later than the currently recommended anticoagulation timing.