Antibiotics Resistance Profile of Bacillus cereus Strains Isolated from Soil and Pepper in Brazzaville

Introduction: Bacillus cereus and spores produced in various ecological niches are responsible for toxic infections in humans. This study is conducted to determine the antibiotics resistance profile of B. cereus strains isolated from soil and pepper consummated in Brazzaville. Methodology: An antimicrobial susceptibility test of 16 B. cereus strains from soil and peppers was performed using 11 antibiotics by the Kirby-Bauer’s diffusion on disc method. Results: Results revealed 100% (16/16) of resistance in penicillin G, amoxicillin, ceftazidime, rifampicin, and colistin, also 18.75% (3/16), 11.76% (2/16), and 18.75% (3/16) of resistance in doripenem, vancomycin and chloramphenicol respectively. In addition, we have observed 100% (16/16), 81.25% (13/16), 76.47% (13/16), 35.29% (5/16), 35.50% (6/16), and 12.5% (2/16) of sensitivity to line-zolid, tigecycline, ciprofloxacin, vancomycin, doripenem and chloram-phenicol respectively. However, all strains have been multidrug resistant (MDR) to betalactams, polypeptides, and ansamycins. Moreover, 7 strains (43.75%) have been variably multiresistant. One strain, Ri10 has been resistant to beta-lactams, polypeptides, ansamycins, cyclins and glycopeptides. No strain was ultraresistant (XDR) or largely insensitive (PDR) to different antibiotics. Conclusion: This study reveals that 51% of strains have been resistant to antibiotics, 32% are sensitive, and 17% have intermediate resistance. These results partly explain the high rate of gastroenteritis observed in Brazzaville due to food poisoning.

Study Frequency of Antibiotic Resistance Enzymes in Bacillus Species in Some of Foods

The subject of this study was to survey prevalence Beta lactamase enzyme in Bacillus species isolated from foods in Isfahan city in Iran. This is a laboratory study performed during 2009-2010 years in Isfahan. In this study, 150 samples of food, including juice ketchup, mayonnaise,

Enhanced removal of antibiotic resistance genes during chicken manure composting after combined inoculation of Bacillus subtilis with biochar

This study explored the combined effects of Bacillus subtilis inoculation with biochar on the evolution of bacterial communities,antibiotic resistance genes(ARGs),and mobile genetic elements(MGEs)during the composting of chicken manure.The results showed that B.subtilis inoculation combined with biochar increased bacterial abundance and diversity as well as prolonged the compost thermophilic period.Promoted organic matter biodegradation and facilitated the organic waste compost humification process,reduced the proliferation of ARGs by altering the bacterial composition.Firmicutes and Actinobacteriota were the main resistant bacteria related to ARGs and MGEs.The decrease in ARGs and MGEs was associated with the reduction in the abundance of related host bacteria.Compost inoculation with B.subtilis and the addition of biochar could promote nutrient transformation,reduce the increase in ARGs and MGEs,and increase the abundance of beneficial soil taxa.

The Five Years Surveillance and Trends of Antibiotic Resistance in Some Common Gram Negative Bacteria at the Vietnam Military Hospital

The study is to identify trends and levels of antibiotic resistance of some common Gram-negative strains over time. The samples were collected from Vietnam Military Hospital 103 between 2014 and 2019. A total of 405 Acinetobacter baumannii., 528 Pseudomonas aeruginosa, 741 Escherichia coli, and 352 Klebsiella pneumoniae strains were identified and antimicrobial susceptibility was by Vitek system and Etest method. The multi-drug resistance (MDR) was major proportion of four common bacteria. In particular, there is a tendency to shift from MDR to Extended drug resistance (XDR) or possibly Pan drug resistant (pPDR). A. baumannii had the highest level of antibiotic resistance, namely, carbapenem (61.5% - 82.5%) and cephalosporin (72.7% - 88.7%). P. aeruginosa resisted most of commonly antibiotics, ranging from 50% to 70%. E. coli had a high resistance with antibiotics like ampicillin (87.2% - 97.6%) and the 3rd generation cephalosporins (up to 79.6%). K. pneumoniae resisted carbapenem from 14.7% to 44.4%, and other antibiotics with the higher rate of 40%. The collected data will be a prerequisite for further studies on mechanisms and factors related to antibiotic resistant bacteria, in order to find out a rational and effective using strategy of antibiotics.

Isolation and Antibiotic-Resistant Pattern of Opportunistic Infectious Microbes from the Infected Sites of Oral Cancer Patients Compared to That of Healthy People Oral Microbiota

Introduction: Oral cancer is the third most prominent type of cancer in Bangladesh. During or after oral cancer treatment, immune-compromised cancer patients may be susceptible to an infection by multi-drug-resistant opportunistic microbes. This study aims to identify the prevalent microorganisms from the infected site of oral cancer patients and observe their antibiotic susceptibility pattern. Materials and Methods: Clinical samples were collected from the infected sites of oral cancer patients and healthy people. The swabs collected were placed on nutrient agar slant, then incubated for 24 hours at 37ºC. Bacteria from the slant were inoculated in several selective media (Mannitol Salt Agar Media, KF Streptococcus Agar media, Cetrimide Agar, Eosin Methylene Blue Agar). Several biochemical tests identified opportunistic microorganisms. Finally, the antibiotic susceptibility test was performed by the Kirby Bauer disc diffusion method. Results: The study found that 65.4% of microbes isolated from the patients’ oral cavities were Gram-negative bacteria, and 34.6% were Gram-positive bacteria. Among the patient group isolates (n = 55), the most prevalent organism was Pseudomonas spp. (30;54.54%). Others were Klebsiella spp. (27;49.09%), Staphylococcus spp. (24;43.63%), E. coli (14;25.45%), Streptococcus spp. (14;25.45%), Proteus spp. (12;21.8%) and Enterococcus spp. (6;10.90%). Both Gram-positive and Gram-negative microbes from the patient group have shown high resistance to the commonly used antibiotics. In the control group (n = 50), the most prevalent organism was Staphylococcus spp. (15;30%). Other organisms were Streptococcus spp. (6;12%), Klebsiella spp. (11;22%), E. coli (3;6%), Streptococcus spp. (14;25.45%), Pseudomonas spp. (8;16%). The microbes of the control group showed less resistance to the antibiotics and rather showed sensitivity to them. Conclusion: The study revealed a high prevalence of multi-drug-resistant opportunistic microbes on immune-compromised oral cancer patients compared to microbes isolated from healthy people’s oral cavity.

DNA fingerprinting of Bacillus cereus from diverse sources by restriction fragment length polymorphism analysis

Bacillus cereus is an opportunistic pathogen causing food poisoning manifested by diarrhoeal or emetic syndrome. It is closely related to animal and human pathogens Bacillus anthracis and the insect pathogen Bacillus thuringiensis. In the present study, antibiotic resistance, heavy metal tolerance &molecular typing of Bacillus cereus from diverse sources such as soil, sewage water, air, fresh water, sea water and milk were studied. Bacillus cereus resistant to Penicillin (10 units/ml) and Amoxycillin (10 µg/ml);sensitive to Cobalt and Mercury even at 1 mM concentration were determined. All the isolate had plasmid ranging in number from 3-5 and their molecular weight ranged from 3.0 kb-2.0 kb. Plasmid DNA band specific to 6,557 bp has been found in Bacillus cereus isolated from sewage water, air, fresh water, sea water and milk.

婴幼儿配方乳粉及婴幼儿米粉中的蜡样芽胞杆菌流行情况、耐药性及分子特征研究

目的 了解流通环节市售婴幼儿配方乳粉和婴幼儿米粉中的蜡样芽胞杆菌流行情况、抗生素耐药性和毒力基因等分子特征。方法 采用GB4789.14—2014《食品安全国家标准食品微生物学检验蜡样芽胞杆菌检验》对样品中的蜡样芽胞杆菌进行检测与生化鉴定。进一步通过抗生素敏感实验和全基因组测序对11株代表性分离株进行研究,获得耐药表型及耐药、毒力基因等分子特征信息。结果 婴幼儿配方乳粉和婴幼儿米粉中蜡样芽胞杆菌的检出率分别为11.97%(56/468)和20.74%(28/135)。11株代表性蜡样芽胞杆菌均为多重耐药菌株,全基因组测序结果发现11株分离株共携带8个耐药基因和14个毒力基因,其中主要携带磷霉素、β-内酰胺类抗生素抗性基因,以及肠毒素基因(hbl和nhe),另发现1株携带ces基因簇蜡样芽胞杆菌菌株。多位点序列分型表明,11株分离株具有遗传多样性,分属10个ST型。结论 婴幼儿配方乳粉和婴幼儿米粉中的蜡样芽胞杆菌检出率较低,但代表菌株的耐药谱和遗传特征具有多样性,应进一步加强监测及采取有效措施进行控制,以保障相关食品的安全性。

Antibacteria Activity of Peganum harmala and Haloxylon salicornicum Leaves Extracts

The use of antibiotics in humans and animals has been marked as a significant step in health due to their effectiveness in controlling and treating bacterial infections. The misuse and overuse of antibiotics have been identified as risk factors for bacterial resistance since microorganisms adapt and develop mechanisms to defend against antibiotics. According to the Centers for Disease Protection and Control (CDC), around 23,000 individuals die every year in the United States due to antibiotic resistance complications. As a result, a demand for alternative treatments has been a goal for scientists as the microbes adapt to selective pressure. The aim of this study is to test the antibacterial activity of leaf extracts of Peganum harmala and Haloxylon salicornicum on both Gram-positive and Gram-negative bacteria on various mediums. The results of the study showed that both P. harmala and H. salicornicum inhibited the bacterial growth in two different media. The results were also compared with different common antibiotics used in both human’s and animal’s fields and showed a promising outcome as alternative antibiotics.

Detection,isolation,and identification of cadmium-resistant bacteria based on PCR-DGGE

This study focused on the screening of cadmium-resistant bacterial strains from Pb-Zn tailing. We investigated the diversity of microbial community inhabiting Dong-san-cha Pb-Zn tailing in Beijing, China, by polymerase chain reaction-denaturing gradient gel electrophoresis （DGGE） of 16S rRNA gene of bacterial strain, and found two dominant strains in the DGGE profile. Using special culture media, we isolated two strong cadmium-resistant bacterial strains. On the basis of morphological, physiological, and biochemical characteristics, BIOLOG, and 16S rDNA sequencing, the two strains were identified as Bacillus cereus and Enterobacter cloacae. Minimal inhibitory concentrations （MICs） of heavy metals for the bacteria were determined. E. cloacae showed higher MIC values for heavy metals and a larger range of antibiotic resistance than B. cereus.

Microbiological safety of spices and their interaction with antibiotics:implications for antimicrobial resistance and their role as potential antibiotic adjuncts

Objectives:A study was undertaken to:1.examine contaminating bacteria on a variety of spices purchased at retail market;2.investigate if spice bacterial enrichments alter the phenotype of 13 bacterial foodborne and clinical pathogens and 1 probiotic organism;and 3.investigate if spices can alter antimicrobial activity of seven clinical antibiotics against 16 bacterial foodborne/clinical pathogens.Materials and Methods:Microbiological examination was undertaken employing 27 spice varieties with four antibiotics and 15 bacterial pathogens.Results:Bacteriological contamination levels varied amongst spice varieties,ranging from Kasmin chilli powder(7.5×10^(6)cfu/g;log10^(6).88 cfu/g)to ginger(1.5×10^(4)cfu/g;log_(10)4.18 cfu/g);mean contamination was 1.38×10^(6)cfu/g(log_(10)6.14 cfu/g).Four species within the genus Bacillus were identified(Bacillus megaterium,Bacillus subtilis,Bacillus licheniformis,and Bacillus cereus).There was no phenotypic difference with the 14 bacteria,with bacterial colony growth/proliferation,pigment production,or with adhesin and mucoid production.None of the spice cultures inhibited any of the 14 bacterial species examined.In the case of doxycycline,amoxicillin,colistin,erythromycin,and piperacillin/tazobactam,the zone of inhibition increased with the inclusion of the 26 spice varieties,suggesting that the spices were interacting synergistically with the antibiotic,thus making the antibiotic more potent against the bacteria tested.Conclusions:This study demonstrates a positive interaction between spices and conventional antibiotics.Given the burden of antimicrobial resistance(AMR)worldwide,but particularly in South Asian countries(India and Pakistan),any food-related innovation that can help maximize the potency of existing antibiotics is to be encouraged and developed.The specific mechanism as to how spices increase the potency of antibiotics needs to be elucidated,as well as novel food(spice)delivery modalities including novel medicinal foodstuffs or functional foods,that can harness this beneficial effect for medicine and society.

炭疽芽孢杆菌携带前噬菌体的预测及耐药性与毒力分析

【目的】预测并分析炭疽芽孢杆菌携带前噬菌体的比例、前噬菌体携带抗生素耐药基因与毒力基因的情况,了解并分析炭疽芽孢杆菌前噬菌体对菌株耐药性与毒力的影响,为后续研究与应用炭疽芽孢杆菌前噬菌体提供借鉴。【方法】利用PHASTER在线分析软件预测炭疽芽孢杆菌携带的前噬菌体,采用抗生素耐药基因数据库(comprehensive antibiotic research database,CARD)和毒力因子数据库(virulence factors database,VFDB)预测前噬菌体携带的抗生素耐药基因和毒力因子。【结果】预测到1421条炭疽芽孢杆菌前噬菌体,其中完整型前噬菌体267条,疑似型前噬菌体321条,不完整型前噬菌体833条。每株炭疽芽孢杆菌所携带的全部前噬菌体基因组占其基因组比例为3%~4%。771条前噬菌体携带1075个耐药基因。耐药表型共有29种,分别来自28种不同的耐药家族,涵盖6种抗生素耐药的作用机制。394条前噬菌体编码688个毒力因子,归类为71种毒力基因和52种毒力因子。分析毒力因子可能的宿主菌株来源构成发现,除炭疽芽孢杆菌外,嗜肺军团菌亚种、蜡样芽孢杆菌、苏云金芽孢杆菌等也有较高的结构比例,是毒力因子可能的宿主来源。【结论】炭疽芽孢杆菌普遍携带前噬菌体,但前噬菌体基因组在炭疽芽孢杆菌基因组中所占的比例较低。约54%前噬菌体携带抗生素耐药基因,以膦酸类、β-内酰胺类抗生素等为主。约28%前噬菌体携带毒力基因。前噬菌体在炭疽芽孢杆菌抗生素耐药基因的获取与传递、毒力基因的获得与传播及致病性演变过程中可能发挥着一定作用。

生牛乳中耐药芽孢杆菌的分离鉴定及四环素抗性基因tetL定位研究

为检测生牛乳中耐热芽孢杆菌的耐药性并定位耐药基因,本研究对34个生牛乳样品分离的芽孢杆菌抗生素耐药性进行研究。耐药实验结果表明:66株芽孢杆菌在固有抗生素耐药性中氨苄西林耐药率高达71.21%,青霉素耐药率高达75.75%。在获得性耐药中7株芽孢杆菌具有克林霉素抗性,1株沙福芽孢杆菌具有红霉素抗性,5株蜡样芽孢杆菌具有四环素抗性。获得性耐药的菌株中,四环素抗性的蜡样芽孢杆菌S7和S11携带有质粒。进一步通过芽孢杆菌四环素耐药基因的PCR筛查及测序分析,确定S7和S11中四环素抗性基因为tetL。通过反向PCR及DNA测序确定蜡样芽孢杆菌S7的tetL基因位于质粒pBCs7上。进一步的序列分析表明质粒pBCs7能够编码的移动蛋白Mob,而Mob蛋白一般能够介导质粒的接合转移。因此,推测质粒pBCs7可能具有转移性,蜡样芽孢杆菌S7的tetL基因存在水平转移风险。

碳青霉烯耐药G-杆菌分布特征及其与抗菌药物使用强度相关性分析

目的探讨碳青霉烯耐药革兰阴性杆菌(CRO)耐药特征以及与碳青霉烯类抗菌药物使用强度(AUD)之间的相关性。方法统计北京清华长庚医院2016—2020年分离的CRO临床资料以及同期碳青霉烯类药物使用情况,分析两者之间的相关性。结果临床共分离出CRO菌株3342株,其中以碳青霉烯耐药肺炎克雷伯菌(CRKP)1280株(38.30%)、碳青霉烯耐药鲍曼不动杆菌(CRAB)1094株(32.73%)、碳青霉烯耐药铜绿假单胞菌(CRPA)609株(18.22%)、碳青霉烯耐药大肠埃希菌(CREC)136株(4.07%)为主;分布科室主要有重症医学科1423株(42.58%)、普内科406(12.15%)、肝胆胰外科310(9.28%)等;2016—2020年CRO、CRKP、碳青霉烯耐药阴沟肠杆菌检出率均呈逐年上升趋势,其检出率与美罗培南使用强度呈强相关(r=0.90、0.90、1.00);而CRAB、CRPA检出率与美罗培南呈中度相关(r=0.50、0.70);CREC检出率与亚胺培南呈中度相关(r=0.50)。结论CRO尤其是CRKP、碳青霉烯耐药阴沟肠杆菌耐药率仍处于不断上升趋势,且与美罗培南的使用强度呈强相关性,临床应加强此类抗菌药物应用管理,遏制CRO的增长。

2008年重庆大坪医院细菌耐药性监测

目的了解本院2008年临床分离病原菌对常用抗菌药物的耐药情况。方法采用纸片扩散法进行抗菌药物敏感性试验,以WHONET5.4软件进行数据分析。结果3303株临床分离病原菌中,革兰阳性球菌占35.5%(1173/3303),革兰阴性杆菌占64.5%(2130/3303)。非ICU前10位病原菌依次为:铜绿假单胞菌、凝固酶阴性葡萄球菌、大肠埃希菌、鲍曼不动杆菌、肺炎克雷伯菌、金黄色葡萄球菌、肠球菌属、洋葱伯克霍尔德菌、阴沟肠杆菌、嗜麦芽窄食假单胞菌;ICU前10位病原菌依次为:鲍曼不动杆菌、洋葱伯克霍尔德菌、凝固酶阴性葡萄球菌、金黄色葡萄球菌、肺炎克雷伯菌、大肠埃希菌、铜绿假单胞菌、嗜麦牙窄食假单胞菌、白色念珠菌、阴沟肠杆菌。耐甲氧西林的金黄色葡萄球菌在ICU及非ICU的检出率分别为76.9%、54.9%,而耐甲氧西林的凝固酶阴性葡萄球菌的检出率分别为87.3%、66.3%,均未检出对糖肽类抗生素耐药的革兰阳性球菌。产ESBL大肠埃希菌在ICU、非ICU的检出率分别为77.5%、49.2%;产ESBL肺炎克雷伯菌在ICU和非ICU的检出率为49.0%、38.4%。ICU分离的铜绿假单胞菌和不动杆菌属对大部分抗菌药物的耐药率比非ICU分离株高。结论本院2008年临床分离的病原菌以革兰阴性杆菌为主,碳青霉烯类抗生素对肠杆菌科细菌保持较高活性,非发酵糖菌数量呈上升趋势,ICU比非ICU分离株耐药性严重,多重耐药菌株检出率高。

连续5年医院细菌菌谱变化及革兰阴性杆菌耐药监测结果分析

目的了解医院细菌菌谱及耐药情况,为医院治疗细菌感染性疾病提供可靠依据。方法采用API系统、VITEK2系统对临床分离菌株进行鉴定,采用K-B纸片扩散法及VITEK2系统对所分离的革兰阴性杆菌进行药敏试验,用2004版美国实验室标准化委员会(NCCLS)标准对结果进行判定,用WHONET5.3软件对数据进行统计学分析。结果5年中排在前8位的细菌均为大肠埃希菌、铜绿假单胞菌、克雷伯菌、不动杆菌属、肠杆菌属、凝固酶阴性葡萄球菌、金黄色葡萄球菌及肠球菌,但排列的顺序有所变化,监测的18种抗菌药物均有不同程度的耐药,而且耐药率呈逐渐上升的趋势。结论了解该医院的菌谱情况及耐药情况对临床治疗感染性疾病十分必要。

我院1999～2001年革兰氏阴性杆菌分布及耐药性变迁分析

目的了解革兰氏阴性杆菌的流行分布及耐药谱的变化,为临床合理选用抗生素提供依据。方法对我院1999～2001三年间革兰氏阴性杆菌耐药性变迁进行回顾性统计分析。结果革兰氏阴性杆菌三年检出率分别为64.3%、58.7%、53.7%;克雷伯氏菌对头孢噻肟的耐药率增长了13.8%,大肠埃希氏菌对环丙沙星的耐药率增长了13.6%,铜绿假单胞菌对亚胺培南耐药率增长了8.4%,阿米卡星耐药率变化不大;产ESBLs的大肠埃希氏菌和克雷伯氏菌分别从21.5%、20.2%上升至28.8%、31.7%。结论三年间临床分离致病菌都以革兰氏阴性杆菌为主,但检出率有逐年下降趋势;肠杆菌科细菌比例下降,不动杆菌属和嗜麦芽寡养单胞菌比例增加;抗生素的耐药性普遍增加;ESBLs检出率明显增加。

短小芽孢杆菌BX-4抗生素标记及定殖效果研究

为研究短小芽孢杆菌BX-4在作物根际的定殖及防病效果，通过浓度梯度法用氨苄青霉素对其进行了抗性标记，并通过番茄盆栽试验研究了其在根际土壤中的定殖规律。结果表明，筛选出的突变体菌株BX-4＇能够耐受浓度为200 μg·mL^-1的氨苄青霉素，并且具有耐药和遗传双重稳定性；应用试验显示该突变体菌株能成功在番茄根际定殖，接种20 d后根际土壤中存活数量达到最高值1.34×10^8 cfu·g^-1干土，以后逐渐下降，到50 d时趋于稳定；筛选的突变体菌株对番茄青枯病具有明显的防治效果，防效达37.9%-50.9%。短小芽孢杆菌BX-4在作物根部的定殖规律为揭示其生防机理及应用该菌提供了科学根据。

生态养猪模式中发酵床优势细菌的微生物学性质及其应用研究

从生态养猪模式的发酵床中分离纯化到14株优势好氧细菌,通过形态学、16S rDNA序列分析和同源性比较,鉴定均为芽孢杆菌属不同的种。发酵试验和饲养试验表明,这些菌株在猪粪和垫料组成的发酵床生长优势强,耐发酵高热,能够产生多种与猪粪降解相关的酶类,除臭效果明显;对某些病原菌具有抑制作用,对猪安全并有促进生长的功能,随着在发酵床饲养时间的延长,从对应猪分离的大肠杆菌的抗药性逐渐降低。生态养猪模式是安全环保节约的饲养模式,可以降低大肠杆菌的抗药性,减少药残。

中医院革兰阴性杆菌的临床分布与耐药分析

目的了解2013年度中医院分离革兰阴性杆菌的临床分布及耐药现状,指导临床医师合理用药。方法对2013年1—12月培养分离的革兰阴性杆菌及其耐药性进行统计分析。结果 2013年医院分离革兰阴性杆菌共1 401株,居首位的是大肠埃希菌381株,占27.2%;余依次为肺炎克雷伯菌311株,占22.2%;铜绿假单胞菌249株,占17.8%;鲍曼不动杆菌194株,占13.8%;肠杆菌属114株,占8.1%。革兰阴性杆菌对亚胺培南、阿米卡星、含β内酰胺酶抑制剂的复合制剂耐药率相对较低;对头孢菌素、庆大霉素、环丙沙星的耐药率相对高。未检出耐亚胺培南的肠杆菌科细菌。该研究中大肠埃希菌超广谱β内酰胺酶(ESBL)检出率为45.4%,肺炎克雷伯菌ESBL检出率为42.1%;产ESBL的大肠埃希菌、肺炎克雷伯菌及鲍曼不动杆菌多表现为多重耐药。结论了解中医院革兰阴性杆菌的临床分布及耐药特点,指导临床医师根据药敏结果合理使用抗菌药物非常重要。

磺胺类耐药菌中抗性基因sul的表达规律

抗生素环境污染是影响抗生素抗性基因传播和扩散的主要因素,然而关于抗生素耐药菌在抗生素暴露下抗性基因的表达机制研究甚少。本研究利用RT-PCR方法检测了土壤中优势耐药菌菌株炭疽芽孢杆菌(Bacillus anthracis SYN201,G+)和弗氏志贺菌菌株(Shigella flexneri NJJN802,G-)在含有不同浓度磺胺类药物的培养基中生长不同时间后抗性基因(sul 1、sul 2、sul 3)的表达变化。结果发现:无论培养基中是否存在磺胺类药物,菌株SYN201和NJJN802中的3种磺胺类抗性基因均分别在培养的第72小时或36小时出现一个明显的表达峰,而在其他培养时间下不表达或表达量处于相对极低的水平;磺胺嘧啶的存在有助于提高菌株在此特征表达时间下抗性基因的表达水平,与未加磺胺嘧啶组相比,暴露于磺胺嘧啶(60μg·m L^(-1))组的sul 1、sul 2和sul 3在菌株SYN201中的相对表达量分别提高了2.5、4.8和3.2倍,而在菌株NJJN802中的相对表达量分别提高了3.7、6.0和5.0倍。通过将耐药菌暴露于不同磺胺嘧啶浓度下考察sul基因相对表达情况,研究发现随着培养基中磺胺嘧啶浓度的升高(0~1 024μg·m L^(-1)),菌株SYN201和NJJN802中sul基因的表达量整体上呈现出明显的上升趋势。本研究对揭示磺胺耐药菌的抗性表达规律及抗生素暴露对其抗性表达发挥的作用具有重要意义。