1.Effects of Different Sequential Enzymatic Cleavage of Trypsin and LysC on Proteomic Sample Preparation
Rui-Dong LI ; Min WANG ; Lu-Lu WANG ; Ming-Ya ZHANG ; Yuan GAO ; Min-Jia TAN ; Fang GUO ; Lin-Hui ZHAI
Chinese Journal of Biochemistry and Molecular Biology 2024;40(11):1618-1626
In mass spectrometry-based proteomics experiments,achieving high-throughput and efficientproteolytic digestion is crucial to ensure optimal protein cleavage and enhance the depth of protein identi-fication (including the number of identified proteins and the coverage of protein amino acid sequences) .Trypsin is the most widely used protease in mass spectrometry-based proteomics due to its ability to spe-cifically cleave the carboxyl terminus of arginine and lysine.However,it was found that Trypsin has some missed enzymatic efficiency for the cleavage of lysine residues.Therefore,in actual proteomics sample preparation,a combination of Trypsin and LysC will be used to ensure adequate cleavage of lysine resi-dues.Our study revealed that the commonly employed LysC-Trypsin tandem cleavage method exerts an impact on the enzymatic cleavage of protein samples by Trypsin due to the subsequent cleavage of Trypsin by initially added LysC.Consequently,we adjusted the order of LysC and Trypsin tandem digestion,with Trypsin cleavage being performed first followed by the addition of LysC to target any missed lysine resi-dues.We comprehensively compared and analyzed three distinct sequential digestion methods,namely Trypsin-Trypsin (T-T),LysC-Trypsin (L-T),and Trypsin-LysC (T-L),in terms of their effects on pro-tein sample preparation quality.The results demonstrated that the Trypsin-LysC sequential digestion ap-proach not only minimizes missed protein lysine/arginine cleavage sites without increasing experimental costs,at the same time yielding peptides with a moderate amino acid sequence length.The use of Tryp-sin-LysC digestion enhances the adsorption and separation of peptide samples in RP-HPLC,as well as improves the depth of protein detection and amino acid sequence coverage during tandem mass spectrome-try analysis.This research work offers a novel technical solution and serves as a valuable reference for proteome sample preparation.
2.A survey on the knowledge of Helicobacter pylori infection diagnosis and treatment among medical staff from general hospitals in Hainan Province
Hui ZHOU ; Guoning CHEN ; Yang GUO ; Yan TAN ; Cheng LAN ; Donghan WU ; Zhanliang MA ; Peng CHENG ; Cuiyi MO ; Ming WANG ; Peiyuan LI ; Ya LIN ; Yongqiang YANG ; Junling HAN ; Zhai CHEN ; Changling LIN ; Zhaona WU ; Shengxiong CHEN ; Zhengyi CHEN ; Xiaoxi HUANG
Chinese Journal of Digestion 2024;44(4):223-233
Objective:To investigate the knowledge of Sixth Chinese national consensus report on the management of Helicobacter pylori infection ( treatment excluded) (hereinafter referred to as sixth national consensus) and 2022 Chinese national clinical practice guideline on Helicobacter pylori eradication treatment (hereinafter referred to as the guideline)among medical staff from general hospitals in Hainan. Methods:From February 20 to May 7, 2023, a questionnaire survey on the diagnosis and treatment of Helicobacter pylori ( H. pylori) infection was conducted among 1 463 medical staff from 15 general hospitals in Hainan Province. The questionnaire was drawn up according to the sixth national consensus and the guideline, covering knowledge of 6 sections, induding H. pylori related diseases, detection of H. pylori, eradication, prevention and influence factors of eradication of H. pylori, etc. Chi-square test was used for statistical analysis. Results:A total of 1 463 valid questionnaires were collected with the effective responsive rate of 100.00%.The 1 463 subjects included 225 gastroenterologists and 1 238 other medical staff(including 503 physicians from other departments, 264 surgeons and 471 medical technologists and pharmacists). About 78.67%(177/225)of gastroenterologists agreed that the overall infection rate of H. pylori in China was more than 20%, the awareness rate was higher than that of other medical staff (physicians from other departments 65.41%(329/503), surgeons 61.74%(163/264), medical technologists and pharmacists 60.30%(284/471); the following datas were sorted by this position), and the difference was statistically significant ( χ2=30.97, P<0.001). About 51.11%(115/225) of gastroenterologists considered that H. pylori serological antibody test could not be used as a diagnostic method for current infection, the awareness rate was higher than that of other medical staff(22.07%(111/503), 14.02%(37/264), 12.31%(58/471)), and the difference was statistically significant( χ2 =152.66, P<0.001). Proton pump inhibitor and potassium-competitive acid blocker should be discontinued for 2 weeks, and antibiotics and bismuth should be discontinued for 4 weeks before urea breath test, and the awareness rates of gastroenterologists were higher than those of other medical staff (38.67%(87/225) vs. 23.26%(117/503), 19.70%(52/264), 18.47%(87/471); 60.89%(137/225) vs. 26.64%(134/503), 25.76%(68/264), 23.78%(112/471)), and the differences were statistically significant ( χ2 =133.70 and 165.51, both P<0.001). For refractory H. pylori infection, 98.67%(222/225)of gastroenterologists agreed with the individualized diagnosis and treatment of H. pylori infection should be guided by bacterial culture, antibiotic susceptibility test or drug resistance gene test, and the awareness rate was higher than that of other medical staff (91.85%(462/503), 93.56%(247/264), 93.21%(439/471)), and the difference was statistically significant( χ2=20.55, P=0.002). About 70.67% (159/225) of gastroenterologists recommended a bismuth containing quadruple regimen, 80.44% (181/225) supported a 10 to 14 day H. pylori eradication course, and the awareness rates were higher than other medical staff (46.92%(236/503), 33.33%(88/264), 32.91%(155/471); 67.20%(338/503), 59.09%(156/264), 53.93%(254/471)), and the differences were statistically significant ( χ2=111.25 and 59.99, both P<0.001). The understanding rates of the sixth national consensus and the guideline in gastroenterologists was 85.33% (192/225), which was higher than that of other medical staff (64.21%(323/503), 66.67%(176/264), 57.96%(273/471)), and the difference was statistically significant ( χ2=85.47, P<0.001). Conclusions:Gastroenterologists from general hospitals in Hainan Province have a better understanding of the sixth national consensus and the guideline than other medical staff. However, there is still a lack of deep understanding of the sixth national consensus and the guideline, and it is necessary to further strengthen the learning and application of the sixth national consensus and the guideline.
3.The Mechanism of Zhuangxuan Yin in the Treatment of Children with H1N1 Pneumonia Through Regulating Gut Microbiota Mediated by p38 MAPK Signaling Pathway
Min ZOU ; Yang ZHAI ; Xiaoping MEI ; Guijiang JIANG ; Ya HUANG ; Yun ZHANG
Traditional Chinese Drug Research & Clinical Pharmacology 2024;35(7):963-970
Objective To explore the mechanism of Zhuangxuan Yin in the treatment of children with H1N1 pneumonia through regulating gut microbiota mediated by p38 mitogen-activated protein kinase(p38-MAPK)pathway.Methods A BALB/c mouse model of H1N1 pneumonia was prepared using the H1N1 influenza virus allantoic solution for nasal drop.The model was randomly separated into 5 groups:model group,Zhuangxuan Yin low-,medium-and high-dose groups,and high-dose Zhuangxuan Yin(28.66 g·kg-1)+anisomycin(10 mg·kg-1)group.The control group was infused with sterile physiological saline of equal volume using the same method.After treatment with Zhuangxuan Yin and anisomycin,the lung index of mice in each group was measured,and HE staining was applied to detect the pathological morphology of lung and large intestine tissues.16SrRNA gene sequencing was applied to detect the structural difference of gut microbiota in mice of each group.Enzyme-linked immunosorbent assay(ELASA)was applied to measure the levels of tumor necrosis factor-α(TNF-α),interleukin(IL)-4,IL-6,and IL-1β in bronchoalveolar lavage fluid(BALF)and large intestine tissue of mice in each group.Western Blot was applied to detect the expression of p38-MAPK pathway-related proteins in lung and large intestine tissues of mice in each group.Results Compared with the control group,the lung and large intestine tissues of the model group mice showed obvious pathological damage,the lung index,pathological score of lung and large intestine,ACE index,Shannon index,abundance of class Clostridia,the levels of TNF-α,IL-4,IL-6,and IL-1β in BALF and large intestine tissues,and p-p38-MAPK/p38-MAPK in lung and large intestine tissues increased(P<0.05).The abundance of class Bacteroidales decreased(P<0.05).Compared with the model group,the pathological damage in the lung and large intestine tissues of mice in the Zhuangxuan Yin low-,medium-and high-dose groups were reduced.The lung index,pathological score of lung and large intestine,ACE index,Shannon index,abundance of class Clostridia,the levels of TNF-α,IL-4,IL-6,and IL-1β in BALF and large intestine tissues,and p-p38-MAPK/p38-MAPK in lung and large intestine tissues decreased(P<0.05),the abundance of class Bacteroidales increased(P<0.05),and in a dose-dependent manner(P<0.05).Compared with the high-dose Zhuangxuan Yin group,the pathological damage in the lung and large intestine tissues of mice in the high-dose Zhuangxuan Yin+anisomycin group was aggravated,the lung index,pathological score of lung and large intestine,ACE index,Shannon index,abundance of class Clostridia,the levels of TNF-α,IL-4,IL-6,and IL-1β in BALF and large intestine tissues,and p-p38-MAPK/p38-MAPK in lung and large intestine tissues increased(P<0.05),and the abundance of class Bacteroidales decreased(P<0.05).Conclusion Zhuangxuan Yin can improve the imbalance of intestinal microbiota in H1N1 pneumonia mice by inhibiting p38-MAPK signal activation,thereby inhibiting inflammation and reducing lung and large intestine tissue damage in mice,which may have a therapeutic effect on children with H1N1 pneumonia.
4.Study on the potential allergen and mechanism of pseudo-allergic reactions induced by combined using of Reduning injection and penicillin G injection based on metabolomics and bioinformatics
Yu-long CHEN ; You ZHAI ; Xiao-yan WANG ; Wei-xia LI ; Hui ZHANG ; Ya-li WU ; Liu-qing YANG ; Xiao-fei CHEN ; Shu-qi ZHANG ; Lu NIU ; Ke-ran FENG ; Kun LI ; Jin-fa TANG ; Ming-liang ZHANG
Acta Pharmaceutica Sinica 2024;59(2):382-394
Based on the strategy of metabolomics combined with bioinformatics, this study analyzed the potential allergens and mechanism of pseudo-allergic reactions (PARs) induced by the combined use of Reduning injection and penicillin G injection. All animal experiments and welfare are in accordance with the requirements of the First Affiliated Experimental Animal Ethics and Animal Welfare Committee of Henan University of Chinese Medicine (approval number: YFYDW2020002). Based on UPLC-Q-TOF/MS technology combined with UNIFI software, a total of 21 compounds were identified in Reduning and penicillin G mixed injection. Based on molecular docking technology, 10 potential allergens with strong binding activity to MrgprX2 agonist sites were further screened. Metabolomics analysis using UPLC-Q-TOF/MS technology revealed that 34 differential metabolites such as arachidonic acid, phosphatidylcholine, phosphatidylserine, prostaglandins, and leukotrienes were endogenous differential metabolites of PARs caused by combined use of Reduning injection and penicillin G injection. Through the analysis of the "potential allergen-target-endogenous differential metabolite" interaction network, the chlorogenic acids (such as chlorogenic acid, neochlorogenic acid, cryptochlorogenic acid, and isochlorogenic acid A) and
5.The role of endoplasmic reticulum stress in gut-pancreas axis dysfunction in type 2 diabetes
Li-ran LEI ; Ya-xin FU ; Quan LIU ; Jia-yu ZHAI ; Zhu-fang SHEN ; Hui CAO ; Shuai-nan LIU
Acta Pharmaceutica Sinica 2024;59(12):3189-3198
Type 2 diabetes mellitus (T2DM) is a complex metabolic disorder characterized by chronic hyperglycemia, hyperlipidemia, and peripheral insulin resistance. Endoplasmic reticulum stress (ERS), a response to cellular stress, is activated across various tissues during the progression of T2DM, leading to disruptions in protein synthesis. Notably, epithelial and endocrine cells with hormone-secreting functions are particularly vulnerable to functional impairments induced by ERS. The gut-pancreas axis is essential for regulating metabolism and the progression of T2DM. Intestinal epithelial L cells, integral to the intestinal barrier, can secrete the glucagon-like peptide-1 (GLP-1). This hormone promotes insulin secretion from pancreatic
6.Study on the comparative analysis of the efficacy of transmesenteric vein extrahepatic portosystemic shunt and transjugular intrahepatic portosystemic shunt in the treatment of cavernous transformation of portal vein.
Ya Dong ZHU ; Wei Xiao LI ; Ming Zhe CUI ; Heng WANG ; Hai Peng YANG ; Shui Ting ZHAI
Chinese Journal of Hepatology 2023;31(1):90-95
Objective: To compare the safety and efficacy of transmesenteric vein extrahepatic portosystemic shunt (TEPS) and transjugular intrahepatic portosystemic shunt (TIPS) in the treatment of cavernous transformation of the portal vein (CTPV). Methods: The clinical data of CTPV patients with patency or partial patency of the superior mesenteric vein treated with TIPS or TEPS treatment in the Department of Vascular Surgery of Henan Provincial People's Hospital from January 2019 to December 2021 were selected. The differences in baseline data, surgical success rate, complication rate, incidence rate of hepatic encephalopathy, and other related indicators between TIPS and TEPS group were statistically analyzed by independent sample t-test, Mann-Whitney U test, and Chi-square test. Kaplan-Meier survival curve was used to calculate the cumulative patency rate of the shunt and the recurrence rate of postoperative portal hypertension symptoms in both groups. Results: The surgical success rate (100% vs. 65.52%), surgical complication rate (6.67% vs. 36.84%), cumulative shunt patency rate (100% vs. 70.70%), and cumulative symptom recurrence rate (0% vs. 25.71%) of the TEPS group and TIPS group were statistically significantly different (P < 0.05). The time of establishing the shunt [28 (2141) min vs. 82 (51206) min], the number of stents used [1 (12) vs. 2 (15)], and the length of the shunt [10 (912) cm vs. 16 (1220) cm] were statistically significant between the two groups (t = -3.764, -4.059, -1.765, P < 0.05). The incidence of postoperative hepatic encephalopathy in the TEPS group and TIPS group was 6.67% and 15.79% respectively, with no statistically significant difference (Fisher's exact probability method, P = 0.613). The pressure of superior mesenteric vein decreased from (29.33 ± 1.99) mmHg to (14.60 ± 2.80) mmHg in the TEPS group and from (29.68 ± 2.31) mmHg to (15.79 ± 3.01) mmHg in TIPS group after surgery, and the difference was statistically significant (t = 16.625, 15.959, P < 0.01). Conclusion: The best indication of TEPS is in CTPV patients with patency or partial patency of the superior mesenteric vein. TEPS improves the accuracy and success rate of surgery and reduces the incidence of complications.
Humans
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Portal Vein/surgery*
;
Portasystemic Shunt, Transjugular Intrahepatic/methods*
;
Hepatic Encephalopathy/etiology*
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Treatment Outcome
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Hypertension, Portal/complications*
;
Retrospective Studies
;
Gastrointestinal Hemorrhage/etiology*
7.Screening novel inhibitors of squalene epoxidase and their effects on hepatocellular carcinoma
Liang-qi GUO ; Ya-li LIU ; Xiao TAN ; Ting ZHAI ; De-qiao SHENG ; Ya-yun LIU
Acta Pharmaceutica Sinica 2023;58(9):2707-2714
Squalene epoxidase (SQLE) is a potential target for the treatment of liver cancer. Bioinformatics analysis indicated that the high expression of SQLE was closely related to the clinical stage and poor prognosis of patients with liver cancer. However, the existing inhibitors against SQLE 195 tyrosine residue (Y195) cannot be used clinically due to severe side effects. In this study, 35 small-molecule compounds targeting SQLE 335 tyrosine residue (Y335) were selected by computer virtual screening. Combined with MTT assay, 3 candidate compounds (19#, 31# and 35#) with significant inhibitory effects on the proliferation of Huh7 cell line were obtained. Further studies showed that these 3 compounds could inhibit the migration of Huh7 cells, reduce the contents of total and free cholesterol, up-regulate the expression of tumor suppressor gene PTEN, and down-regulate the expression of PI3K and AKT proteins. The results showed that the novel inhibitors 19#, 31# and 35# targeting SQLE Y335 could reduce cholesterol content, inhibit the proliferation and migration of Huh7, thus playing an anti-liver cancer role.
8.Neutralizing Antibody Responses against Five SARS-CoV-2 Variants and T Lymphocyte Change after Vaccine Breakthrough Infections from the SARS-CoV-2 Omicron BA.1 Variant in Tianjin, China: A Prospective Study.
Ying ZHANG ; Jiang Wen QU ; Min Na ZHENG ; Ya Xing DING ; Wei CHEN ; Shao Dong YE ; Xiao Yan LI ; Yan Kun LI ; Ying LIU ; Di ZHU ; Can Rui JIN ; Lin WANG ; Jin Ye YANG ; Yu ZHAI ; Er Qiang WANG ; Xing MENG
Biomedical and Environmental Sciences 2023;36(7):614-624
OBJECTIVE:
To investigate whether Omicron BA.1 breakthrough infection after receiving the SARS-CoV-2 vaccine could create a strong immunity barrier.
METHODS:
Blood samples were collected at two different time points from 124 Omicron BA.1 breakthrough infected patients and 124 controls matched for age, gender, and vaccination profile. Live virus-neutralizing antibodies against five SARS-CoV-2 variants, including WT, Gamma, Beta, Delta, and Omicron BA.1, and T-lymphocyte lymphocyte counts in both groups were measured and statistically analyzed.
RESULTS:
The neutralizing antibody titers against five different variants of SARS-CoV-2 were significantly increased in the vaccinated population infected with the Omicron BA.1 variant at 3 months after infection, but mainly increased the antibody level against the WT strain, and the antibody against the Omicron strain was the lowest. The neutralizing antibody level decreased rapidly 6 months after infection. The T-lymphocyte cell counts of patients with mild and moderate disease recovered at 3 months and completely returned to the normal state at 6 months.
CONCLUSION
Omicron BA.1 breakthrough infection mainly evoked humoral immune memory in the original strain after vaccination and hardly produced neutralizing antibodies specific to Omicron BA.1. Neutralizing antibodies against the different strains declined rapidly and showed features similar to those of influenza. Thus, T-lymphocytes may play an important role in recovery.
Humans
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Antibodies, Neutralizing
;
Prospective Studies
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SARS-CoV-2
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Breakthrough Infections
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COVID-19 Vaccines
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COVID-19
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T-Lymphocytes
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China/epidemiology*
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Antibodies, Viral
9.Regulatory effect and mechanism of total alkaloids of Rhizoma Corydalis on hippocampal silencing information regulator 1/tumor suppressor P53 protein signaling pathway in rats with chronic cerebral ischemia
Jun LI ; Yazhi QI ; Ya TANG ; Rui CAO ; Yanling ZHAI ; Yusheng HAN ; Qiang XU
Chinese Journal of Cerebrovascular Diseases 2023;20(12):837-845
Objective To investigate the effect of total alkaloids of Rhizoma Corydalis(TAC)on the expression of silencing information regulator 1(Sirt1)/tumor suppressor P53 protein signaling pathway-related proteins in the hippocampus of rats with chronic cerebral ischemia(CCH),and to explore its mechanism.Methods The rats were randomly divided into Sham operation group,model group,TAC high-dose group(14 mg/kg)and TAC low-dose group(7 mg/kg),with 6 rats in each group.A modified bilateral common carotid artery permanent occlusion method(BCCAO)was used to establish a rat model of CCH,and only bilateral common carotid arteries were separated in the Sham group.After the modeling was completed,each group was given the corresponding drug or isotonic saline by gavage,once a day,and the treatment lasted for 14 days.Hematoxycin-eosin staining was used to observe the pathological changes in the hippocampus of rats,in situ terminal deoxynucleotidyl transferase-mediated deoxyuridinetriphate-biotin nick end labeling assay(TUNEL)was used to detect neuronal apoptosis,and Western blotting and immunohistochemistry were used to detect expression of Sirt1,P53,P53 positive apoptosis regulator(PUMA),B-cell lymphocytoma-2(Bcl-2)protein,Bcl-2-related X protein(BAX),respectively in the hippocampus of rats.Results(1)There were significant differences in the number of apoptotic cells and apoptosis rate among the four groups(F-values were 71.417 and 76.835,respectively,both P<0.01).There were statistically significant differences in the mean integral optical density values of Sirt1,P53,PUMA,BAX and Bcl-2 protein positive expression areas among the four groups(F-values were 1 178.390,42.465,867.413,110.656 and 131.801,all P<0.01).There were significant differences in the relative expression levels of Sirt1,P53,PUMA,BAX and Bcl-2 among the four groups(F-values were 9.497,11.863,58.552,186.855 and 12.466,all P<0.01).(2)Compared with the Sham operation group,the neuronal arrangement of brain tissue in the hippocampus of the model group was disordered,the nuclear consolidation increased,and the glial cells and inflammatory cells increased significantly,and the number and apoptosis rate of neurons in the hippocampus of the model group increased significantly(respectively[10.8±1.5]cells vs.[2.0±0.9]cells and[35.5±4.5]%vs.[6.2±2.6]%;both P<0.05),and the average integral optical density values of the positive expression areas of Sirt1 and Bcl-2 proteins decreased significantly(84.6±6.6 vs.244.6±4.9,138.5±6.7 vs.210.9±10.0;both P<0.05),the average integral optical density values of P53,PUMA and BAX proteins were significantly increased(156.8±11.6 vs.93.5±11.6,151.3±3.3 vs.38.0±4.0,87.0±5.0 vs.38.4±5.5;all P<0.05),the relative expression levels of Sirt1 and Bcl-2 proteins were significantly decreased(0.51±0.07 vs.0.74±0.07,0.36±0.03 vs.0.53±0.05;both P<0.05),and the relative expression levels of P53,PUMA and BAX proteins were significantly increased(0.37±0.06 vs.0.21±0.02,0.62±0.06 vs.0.23±0.02,1.08±0.06 vs.0.45±0.03;all P<0.05).(3)Compared with the model group,the hippocampal tissue structure of the high-dose and low-dose TAC groups was relatively compact and uniform,the neurons were neatly arranged,and the cell structure was relatively clear and complete,while the number of neuronal apoptotic cells and the apoptosis rate decreased significantly(respectively[3.8±0.7]cells vs.[6.2±1.2]cells,[12.4±2.8]%vs.[20.2±3.9]%;both P<0.05),and the average integrated optical density values of the positive expression areas of Sirt1 and Bcl-2 proteins(the high-dose and low-dose TAC groups:Sirt1 150.0±4.8,131.3±1.3,and Bcl-2 207.1±7.4,169.5±3.9,respectively)were significantly increased(both P<0.05),the average integral optical density values of P53,PUMA and BAX proteins were significantly decreased(the high-dose and low-dose TAC groups:P53 105.9±8.8,115.5±9.0,and PUMA56.8±5.1,74.4±3.9,and BAX40.5±5.6,48.4±5.0,respectively,all P<0.05),the relative expression levels of Bcl-2 protein(the high-dose and low-dose TAC groups:0.53±0.05,0.47±0.02,respectively)were significantly increased(P<0.05),the relative expression levels of P53(the high-dose and low-dose TAC groups:0.21±0.02,0.24±0.04,respectively),PUMA(the high-dose and low-dose TAC groups:0.36±0.02,0.28±0.04,respectively)and BAX proteins(the high-dose and low-dose TAC groups:0.52±0.02,0.54±0.03,respectively)were significantly decreased(all P<0.05),the relative expression level of Sirt1 protein in the TAC high-dose group was significantly decreased(0.71±0.05,P<0.05),and the relative expression level of Sirt1 protein in the TAC low-dose group was not statistically significant(0.52±0.08,P>0.05).Conclusion TAC can alleviate neuronal damage and reduce the apoptosis rate of neurons in the hippocampus of CCH rats,and the mechanism may be related to the activation of Sirt1/P53 pathway,inhibition of P53 protein activity,and thus the expression level of apoptosis-related proteins in the downstream of TAC.
10.Effects of ppk1 deletion on the drug susceptibility of uropathogenic Escherichia coli producing ESBLs.
Jing Yi OU ; Wan Shan CHEN ; Mei Jun CHEN ; Ling Zhai ZHAO ; Ling Hua LI ; Liang PENG ; Lan LIANG ; Ya Ling SHI
Chinese Journal of Preventive Medicine 2023;57(8):1238-1245
To investigate the effect and the mechanism of ppk1 gene deletion on the drug susceptibility of uropathogenic Escherichia coli producing extended-spectrum beta-lactamases (ESBLs-UPEC). The study was an experimental study. From March to April 2021, a strain of ESBLs-UPEC (genotype was TEM combined with CTX-M-14) named as UE210113, was isolated from urine sample of the patient with urinary tract infection in the Laboratory Department of Guangzhou Eighth People's Hospital, meanwhile its ppk1 gene knock-out strain Δpk1 and complemented strain Δpk1-C were constructed by suicide plasmid homologous recombination technique, which was used to study the effect of ppk1 gene on ESBLs-UPEC drug sensitivity and its mechanism. The drug susceptibility of UE210113, Δpk1, and Δpk1-C were measured by Vitek2 Compact System and broth microdilution method. The quantitative expression of ESBLs, outer membrane protein and multidrug efflux systems encoding genes of UE210113, Δpk1 and Δpk1-C were performed by using qRT-PCR analysis. By using two independent sample Mann-Whitney U test, the drug susceptibility results showed that, compared with UE210113 strain, the sensitivities of Δpk1 to ceftazidime, cefepime, tobramycin, minocycline and cotrimoxazole were enhanced (Z=-2.121,P<0.05;Z=-2.236,P<0.05;Z=-2.236,P<0.05;Z=-2.121,P<0.05), and the drug susceptibility of Δpk1-C restored to the same as which of UE210113 (Z=0,P>0.05). The expression levels of ESBLs-enconding genes blaTEM and blaCTX-M-14 in Δpk1 were significantly down-regulated compared with UE210113, but the expression was not restored in Δpk1-C. The expression of outer membrane protein gene omp F in Δpk1 was significantly up-regulated, while the expression of omp A and omp C were down-regulated. The results showed that the expression of multidrug efflux systems encoding genes tol C, mdt A and mdtG were down-regulated in Δpk1 compared with UE210113. The expression of all of the outer membrane protein genes and the multidrug efflux systems genes were restored in Δpk1-C. In conclusion,the lost of ppk1 gene can affect the expression of the outer membrane protein and multidrug efflux systems encoding genes of ESBLs-UPEC, which increase the sensitivity of ESBLs-UPEC to various drugs.
Humans
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beta-Lactamases/metabolism*
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Uropathogenic Escherichia coli/metabolism*
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Urinary Tract Infections
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Plasmids
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Membrane Proteins/genetics*
;
Escherichia coli Infections
;
Microbial Sensitivity Tests
;
Anti-Bacterial Agents/pharmacology*

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