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1.
PLoS One ; 18(1): e0270945, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36662697

RESUMO

This study aimed to investigate the presence and persistence of antibiotics in wastewater of four typical pharmaceutical manufactories in China and receiving water bodies and suggest the removal of antibiotics by the wastewater treatment process. It also evaluated the environmental impact of antibiotic residues through wastewater discharge into receiving water bodies. The results indicated that thirteen antibiotics were detected in wastewater samples with concentrations ranging from 57.03 to 726.79 ng/L. Fluoroquinolones and macrolides were the most abundant antibiotic classes found in wastewater samples, accounting for 42.5% and 38.7% of total antibiotic concentrations, respectively, followed by sulfonamides (16.4%) and tetracyclines (2.4%). Erythromycin-H2O, lincomycin, ofloxacin, and trimethoprim were the most frequently detected antibiotics; among these antibiotics, the concentration of ofloxacin was the highest in most wastewater samples. No significant difference was found in different treatment processes used to remove antibiotics in wastewater samples. More than 50% of antibiotics were not completely removed with a removal efficiency of less than 70%. The concentration of detected antibiotics in the receiving water bodies was an order of magnitude lower than that in the wastewater sample due to dilution. An environmental risk assessment showed that lincomycin and ofloxacin could pose a high risk at the concentrations detected in effluents and a medium risk in their receiving water bodies, highlighting a potential hazard to the health of the aquatic ecosystem. Overall, The investigation was aimed to determine and monitor the concentration of selected antibiotics in 4 typical PMFs and their receiving water bodies, and to study the removal of these substances in PMFs. This study will provide significant data and findings for future studies on antibiotics-related pollution control and management in water bodies.


Assuntos
Antibacterianos , Poluentes Químicos da Água , Antibacterianos/análise , Ecossistema , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Ofloxacino , Lincomicina , China , Medição de Risco , Água , Preparações Farmacêuticas , Eliminação de Resíduos Líquidos
2.
Mikrochim Acta ; 190(1): 11, 2022 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-36477444

RESUMO

A novel electrochemiluminescence (ECL) aptasensor for the determination of lincomycin (LIN) was developed based on CdS QDs/carboxylated g-C3N4 (CdS QDs/C-g-C3N4). CdS QDs/C-g-C3N4 served as the substrate of the aptasensor, and then CdS QDs/C-g-C3N4-modified electrode was incubated with aptamer DNA (Apt-DNA). When the non-specific sites of the electrode surface was blocked by 6-mercaptohexanol, the ferrocene-labeled probe (Fer-DNA) was assembled onto the electrode surface through base complementation with Apt-DNA. In the absence of LIN, the ECL signal was quenched effectively by Fer-DNA and a decreased ECL emission (off state) was acquired. On the contrary, LIN was specifically bond with Apt-DNA, and Fer-DNA was detached from the aptasensor surface because of the deformation of Apt-DNA, resulting in an effectively enhanced ECL signal (on state). The constructed ECL aptasensor exhibited a wide detection range for LIN determination (0.05 ng mL-1-100 µg mL-1) with a low detection limit (0.02 ng mL-1). Importantly, the proposed ECL aptasensor showed outstanding accuracy and specificity for LIN determination, and also provided a potential strategy for other antibiotic determinations.


Assuntos
DNA , Lincomicina
3.
Int J Mol Sci ; 23(22)2022 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-36430213

RESUMO

The overuse of antibiotics has led to the emergence of resistant bacteria. A good alternative is silver nanoparticles, which have antibacterial activity against Gram-negative and Gram-positive bacteria, including multidrug-resistant strains. Their combination with already known antibiotics has a synergistic effect. In this work, we studied the synthesis of conjugates of silver nanoparticles with two antibiotics, lincomycin and cefazolin. Albumin and glutathione were used as spacer shells with functional groups. The physicochemical properties of the obtained conjugates, their cytotoxicity and synergism of antimicrobial activity were studied. The 50% antimicrobial activity of the obtained samples was shown, which allows them to be recommended for use as topical drug preparations.


Assuntos
Cefazolina , Nanopartículas Metálicas , Cefazolina/farmacologia , Lincomicina/farmacologia , Prata/farmacologia , Prata/química , Nanopartículas Metálicas/química , Testes de Sensibilidade Microbiana , Antibacterianos/farmacologia , Antibacterianos/química
4.
Sci Rep ; 12(1): 20105, 2022 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-36418414

RESUMO

To investigate the bacterial epidemiology of blood cultures taken during the treatment of critically ill burn patients, the use of antibiotics at admission and before the observation of positive blood cultures, and their effect on prognosis. A retrospective study method was used. From January 1, 2010, to December 31, 2019, burn patients who met the inclusion criteria and were treated at the Burn Department, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, were enrolled in the study. Data were collected from the patients' electronic medical records. General patient information, including length of hospital stay, length of intensive care unit (ICU) stay, in-hospital mortality, the bacteria epidemiological characteristics of blood cultures, and the use of antibiotics within 24 h after admission and before a positive blood culture was observed, was collected. Independent sample t tests and χ2 tests were used to compare the effects of a positive blood culture and the use of appropriate antibiotics within 24 h after admission and before the observation of a positive blood culture on prognosis. (1) The three most frequently detected bacteria in the blood cultures were Klebsiella pneumoniae, Pseudomonas aeruginosa, and Acinetobacter baumannii, and the amount of K. pneumoniae detected increased gradually. (2) Compared with the group of patients who were negative for bloodstream infection , the positive bloodstream infection group had a larger total body burn surface area (TBSA) (t = - 5.097, P = 0.000) and third-degree burn area (t = - 5.133, P = 0.000), a significantly longer length of hospital stay (t = 3.003, P = 0.003) and the length of ICU stay (t = 4.258, P = 0.000), and a significantly higher rate of in-hospital mortality (χ2 = 8.485, P = 0.004). When K. pneumoniae was detected, the length of hospital stay (t = 2.148, P = 0.035) and the length of ICU stay (t = 2.880, P = 0.005) were significantly prolonged. (3) The two antibiotics that were most frequently used in patients with acute burns within 24 h after admission were lincomycin (90 cases, 29.32%) and carbapenems (79 cases, 25.73%). Comparing the clinical characteristics of the lincomycin group and the carbapenem group, the TBSA (t = - 3.34, P = 0.001) and the third-degree burn area (t = - 6.08, P = 0.000) of the patients in the carbapenem group were larger, and the length of hospital stay (t = - 2.136, P = 0.035) and length of ICU stay (t = - 5.18, P = 0.000) were longer, but the difference in in-hospital mortality was not statistically significant (χ2 = 1.983, P = 0.159). (4) Comparing the group with appropriate initial antibiotic use within 24 h of admission to the inappropriate use group, the TBSA (t = - 0.605, P = 0.547), the third-degree burn area (t = 0.348, P = 0.729), the length of hospital stay (t = - 0.767, P = 0.445), the length of ICU stay (t = - 0.220, P = 0.827) and in-hospital mortality (χ2 = 1.271, P = 0.260) were not significantly different. (5) Comparing the group with appropriate antibiotic use before a positive blood culture was observed to the group with inappropriate antibiotic use, the TBSA (t = - 0.418, P = 0.677), the third-degree burn area (t = 0.266, P = 0.791), the length of hospital stay, the length of ICU stay (t = 0.995, P = 0.322) and in-hospital mortality (χ2 = 1.274, P = 0.259) were not significantly different. We found that patients with a positive blood culture had a larger burn area and a worse prognosis; that the greater the amount of K. pneumoniae in the bloodstream of burn patients was, the longer the hospital and ICU stays were; that whether appropriate antibiotics were administered to acute critical burn patients 24 h after admission had no effect on the prognosis; and that whether appropriate antibiotics were administered before a positive blood culture was observed had no effect on prognosis.


Assuntos
Queimaduras , Sepse , Humanos , Estado Terminal , Antibacterianos/uso terapêutico , Estudos Retrospectivos , China , Queimaduras/tratamento farmacológico , Prognóstico , Carbapenêmicos , Klebsiella pneumoniae , Lincomicina
5.
Environ Pollut ; 315: 120306, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36181928

RESUMO

The ionic strength of infiltration water changes with the seasonal alternation of irrigation sources. In this study, reactivity changes of birnessite-coated sand with the fluctuations of ionic strength of infiltration water (i.e. from groundwater to rainwater) and the involved mechanism were investigated through column experiments. Birnessite-coated sand was less reactive in groundwater than in rainwater because of the higher cation content and higher pH of groundwater. The cations in the groundwater were adsorbed on birnessite-coated sand and then desorbed in presence of a dilute aqueous solution represented by rainwater. The reactivity of the passivated birnessite-coated sand was recovered instantaneously, and approximately one-third of the pristine reactivity was restored. During recovery, Na+ desorption and lincomycin (LIN) removal both exhibited a two-stage reaction pattern. The LIN removal correlated with Na+ desorption (r = 0.99) so that the reactive sites that were binding 5.602 µmol of Na+ became available for 1 µmol of LIN removal. These results suggest that the reactivity of manganese oxides toward organic contaminant is associated with the ionic strength of infiltration water and indicate that the partial reactivity can be naturally restored.


Assuntos
Areia , Água , Lincomicina , Óxidos/química , Concentração Osmolar , Cátions , Oxirredução
6.
Eur Rev Med Pharmacol Sci ; 26(18): 6837-6844, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36196732

RESUMO

OBJECTIVE: Salmonella isolates have been discovered in many regions of the world. We investigated the prevalence and resistance of Salmonella isolates in raw milk of healthy dairy cows on farms in different regions of Henan Province, China. MATERIALS AND METHODS: From July 2020 to November 2021, 422 raw milk samples were collected. The minimum inhibitory concentrations (MICs) of 16 antimicrobial agents against 89 Salmonella strains detected from the raw milk samples were determined using the broth microdilution method, and the resistance genes for fluoroquinolones were identified using polymerase chain reaction. RESULTS: Eighty-nine (21.09%) Salmonella isolates were recovered from 422 raw milk samples. The Salmonella strains exhibited high resistance to amoxicillin (100.00%), tylosin (95.50%), and lincomycin (95.50%). Additionally, tigecycline showed good activity against Salmonella, with an MIC50 of 0.25 µg/mL. All Salmonella isolates showed multidrug resistance (MDR), and >50% of the strains showed resistance to more than six antimicrobials. The strains from Jiaozuo exhibited 100% resistance to amoxicillin, terramycin, tylosin, and lincomycin. Two efflux pump genes, oqxA and oqxB, had the highest carrying rates of 66.29% and 64.04%, respectively. Additionally, the carrying rates of oqxA and oqxB were high in Shangqiu, Zhengzhou, and Jiaozuo. The carrying rates of aac(6')-Ib-cr in Shangqiu and Zhengzhou were 33.33% and 38.46%, respectively. CONCLUSIONS: This study revealed a high prevalence of Salmonella isolates obtained from raw milk of healthy dairy cows in different regions of Henan Province, China. The Salmonella strains exhibited various degrees of MDR. Salmonella can be transmitted to humans via consumption of contaminated raw milk; thus, the presence of resistance genes poses a potential threat to public health, highlighting the need for vigilant monitoring of Salmonella isolates.


Assuntos
Fluoroquinolonas , Oxitetraciclina , Amoxicilina , Animais , Antibacterianos/farmacologia , Bovinos , China/epidemiologia , Farmacorresistência Bacteriana/genética , Farmacorresistência Bacteriana Múltipla/genética , Humanos , Lincomicina/farmacologia , Testes de Sensibilidade Microbiana , Leite , Fenótipo , Prevalência , Salmonella , Tigeciclina , Tilosina
7.
Antimicrob Agents Chemother ; 66(10): e0067722, 2022 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-36165686

RESUMO

We investigated whether gentamicin resistance (Genr) in Escherichia coli isolates from human infections was related to Genr E. coli in chicken and whether resistance may be due to coselection from use of lincomycin-spectinomycin in chickens on farms. Whole-genome sequencing was performed on 483 Genr E. coli isolates isolated between 2014 and 2017. These included 205 human-source isolates collected by the Canadian Ward (CANWARD) program and 278 chicken-source isolates: 167 from live/recently slaughtered chickens (animals) and 111 from retail chicken meat collected by the Canadian Integrated Program for Antimicrobial Resistance Surveillance (CIPARS). The predominant Genr gene was different in human and chicken sources; however, both sources carried aac(3)-IId, aac(3)-VIa, and aac(3)-IVa. Forty-one percent of human clinical isolates of Genr E. coli contained a blaCTX-M extended-spectrum beta-lactamase (ESBL) gene (84/205), and 53% of these were sequence type 131 (ST131). Phylogenomic analysis revealed a high diversity of Genr isolates; however, there were three small clusters of closely related isolates from human and chicken sources. Genr and spectinomycin resistance (Specr) genes were colocated in 148/167 (89%) chicken animal isolates, 94/111 (85%) chicken retail meat isolates, and 137/205 (67%) human-source isolates. Long-read sequencing of 23 isolates showed linkage of the Genr and Specr genes on the same plasmid in 14/15 (93%) isolates from chicken(s) and 6/8 (75%) isolates from humans. The use of lincomycin-spectinomycin on farms may be coselecting for gentamicin-resistant plasmids in E. coli in broiler chickens; however, Genr isolates and plasmids were mostly different in chickens and humans.


Assuntos
Infecções por Escherichia coli , Saúde Única , Humanos , Animais , Escherichia coli/genética , Galinhas , beta-Lactamases/genética , Espectinomicina/farmacologia , Gentamicinas/farmacologia , Antibacterianos/farmacologia , Canadá/epidemiologia , Infecções por Escherichia coli/tratamento farmacológico , Infecções por Escherichia coli/veterinária , Plasmídeos/genética , Lincomicina , Genômica
8.
Nutrients ; 14(18)2022 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-36145063

RESUMO

Mastitis is an emerging health concern in animals. An increased incidence of mastitis in dairy cows has been reported in the last few years across the world. It is estimated that up to 20% of cows are suffering from mastitis, causing incompetency in the mucosal immunity and resulting in excessive global economic losses in the dairy industry. Staphylococcus aureus (S. aureus) has been reported as the most common bacterial pathogen of mastitis at clinical and sub-clinical levels. Antibiotics, including penicillin, macrolides, lincomycin, cephalosporins, tetracyclines, chloramphenicol, and methicillin, were used to cure S. aureus-induced mastitis. However, S. aureus is resistant to most antibiotics, and methicillin-resistant S. aureus (MRSA) especially has emerged as a critical health concern. MRSA impairs immune homeostasis leaving the host more susceptible to other infections. Thus, exploring an alternative to antibiotics has become an immediate requirement of the current decade. Short chain fatty acids (SCFAs) are the potent bioactive metabolites produced by host gut microbiota through fermentation and play a crucial role in host/pathogen interaction and could be applied as a potential therapeutic agent against mastitis. The purpose of this review is to summarize the potential mechanism by which SCFAs alleviate mastitis, providing the theoretical reference for the usage of SCFAs in preventing or curing mastitis.


Assuntos
Mastite Bovina , Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Animais , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Bovinos , Cefalosporinas/uso terapêutico , Cloranfenicol/uso terapêutico , Ácidos Graxos Voláteis/uso terapêutico , Feminino , Humanos , Lincomicina/uso terapêutico , Macrolídeos , Mastite Bovina/tratamento farmacológico , Mastite Bovina/epidemiologia , Mastite Bovina/microbiologia , Meticilina/uso terapêutico , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus , Tetraciclinas
9.
Sci Rep ; 12(1): 15541, 2022 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-36109627

RESUMO

Staphylococcus equorum strain KM1031 is resistant to chloramphenicol, erythromycin and lincomycin. To shed light on the genetic factors underlying these antibiotic resistances, we determined the global gene expression profile of S. equorum KM1031 using RNA sequencing. During chloramphenicol, erythromycin and lincomycin treatment, 8.3% (183/2,336), 16.0% (354/2,336), and 2.9% (63/2,336) of S. equorum KM1031 genes exhibited significant differences in expression, respectively. These three antibiotics upregulated genes related to efflux and downregulated genes related to transporters. Antibiotic treatment also upregulated osmoprotectant-related genes involved in salt tolerance. To identify specific genes functionally related to antibiotic resistance, we compared the genome of strain KM1031 with those of three S. equorum strains that are sensitive to these three antibiotics. We identified three genes of particular interest: an antibiotic biosynthesis monooxygenase gene (abm, AWC34_RS01805) related to chloramphenicol resistance, an antibiotic ABC transporter ATP-binding protein gene (msr, AWC34_RS11115) related to erythromycin resistance, and a lincosamide nucleotydyltransferase gene (lnuA, AWC34_RS13300) related to lincomycin resistance. These genes were upregulated in response to the corresponding antibiotic; in particular, msr was upregulated more than fourfold by erythromycin treatment. Finally, the results of RNA sequencing were validated by quantitative real-time PCR. This transcriptomic analysis provides genetic evidence regarding antibiotic stress responses of S. equorum strain KM1031.


Assuntos
Alimentos Fermentados , Lincomicina , Transportadores de Cassetes de Ligação de ATP/genética , Trifosfato de Adenosina , Antibacterianos/farmacologia , Cloranfenicol/farmacologia , Eritromicina/farmacologia , Lincomicina/farmacologia , Oxigenases de Função Mista , Staphylococcus , Transcriptoma
10.
Environ Res ; 215(Pt 1): 114237, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36084673

RESUMO

The application of pig slurry as fertilizer in agriculture provides nutrients, but it can also contain veterinary medicines, including antibiotic residues (ABs), which can have an ecotoxicological impact on agroecosystems. Furthermore, uptake, translocation, and accumulation of ABs in crops can mobilize them throughout the food chain. This greenhouse study aims to assess AB uptake from soil fertilized with pig slurry and its phenotypical effects on Lactuca sativa L. The plants were cropped in loamy clay soil dosed at 140 kg total N/ha and containing antibiotics (lincomycin, sulfadiazine, oxytetracycline, and enrofloxacin) at different concentration levels (0, 0.05, 0.5, 5, 50, and 500 mg/kg fresh weight, fw). Whereas sulfadiazine (11.8 ng/g fw) was detected in lettuce leaves at the intermediate doses (0.5 mg/kg), lincomycin and its transformation products (hydroxy/sulfate) were only detected at the 50 mg/kg fw dose. In addition, increased AB doses in the pig slurry resulted in decreased lettuce fresh weight and lipid and carbohydrate content and became lethal to lettuce at the highest AB concentrations (500 mg/kg fw). Nevertheless, even at higher doses, the AB content in lettuce following pig-slurry fertilization did not pose any direct significant human health risk (total hazard quotient<0.01). However, the promotion of antimicrobial resistance in humans due to the intake of these vegetables cannot be ruled out.


Assuntos
Oxitetraciclina , Poluentes do Solo , Agricultura , Animais , Antibacterianos , Argila , Enrofloxacina , Fertilizantes , Fluoroquinolonas , Humanos , Alface , Lincomicina , Lipídeos , Solo/química , Poluentes do Solo/análise , Poluentes do Solo/toxicidade , Sulfadiazina , Sulfanilamida , Sulfatos , Suínos , Tetraciclina
11.
PLoS One ; 17(8): e0272903, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35951622

RESUMO

Mycoplasma hyorhinis is an emerging swine pathogen bacterium causing polyserositis and polyarthritis in weaners and finishers. The pathogen is distributed world-wide, generating significant economic losses. No commercially available vaccine is available in Europe. Therefore, besides improving the housing conditions for prevention, antimicrobial therapy of the diseased animals is the only option to control the infection. Our aim was to determine the minimal inhibitory concentrations (MIC) of ten antimicrobials potentially used against M. hyorhinis infection. The antibiotic susceptibility of 76 M. hyorhinis isolates from Belgium, Germany, Hungary, Italy and Poland collected between 2019 and 2021 was determined by broth micro-dilution method and mismatch amplification mutation assay (MAMA). Low concentrations of tiamulin (MIC90 0.312 µg/ml), doxycycline (MIC90 0.078 µg/ml), oxytetracycline (MIC90 0.25 µg/ml), florfenicol (MIC90 2 µg/ml) and moderate concentrations of enrofloxacin (MIC90 1.25 µg/ml) inhibited the growth of the isolates. For the tested macrolides and lincomycin, a bimodal MIC pattern was observed (MIC90 >64 µg/ml for lincomycin, tulathromycin, tylosin and tilmicosin and 5 µg/ml for tylvalosin). The results of the MAMA assay were in line with the conventional method with three exceptions. Based on our statistical analyses, significant differences in MIC values of tiamulin and doxycycline were observed between certain countries. Our results show various levels of antimicrobial susceptibility among M. hyorhinis isolates to the tested antibiotics. The data underline the importance of susceptibility monitoring on pan-European level and provides essential information for proper antibiotic choice in therapy.


Assuntos
Anti-Infecciosos , Infecções por Mycoplasma , Mycoplasma hyorhinis , Animais , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Anti-Infecciosos/farmacologia , Doxiciclina/farmacologia , Europa (Continente) , Lincomicina/farmacologia , Testes de Sensibilidade Microbiana , Infecções por Mycoplasma/tratamento farmacológico , Infecções por Mycoplasma/microbiologia
12.
Antimicrob Agents Chemother ; 66(8): e0019722, 2022 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-35876576

RESUMO

Methicillin-resistant Staphylococcus lugdunensis (MRSL) strains showing resistance to several common antibiotics have been reported recently. Sequence type (ST) 3 MRSL carrying SCCmec types IV, V, or Vt is the major lineage associated with health care-associated infections. We aimed to investigate the distribution and dissemination of antimicrobial resistance determinants in this lineage. Two representative ST3-MRSL strains, CGMH-SL131 (SCCmec V) and CGMH-SL138 (SCCmec IV), were subjected to whole-genome sequencing. Detection of antibiotic resistance genes and screening of susceptibility patterns were performed for 30 ST3-MRSL and 16 ST6-MRSL strains via PCR and standard methods. Except for mecA and blaZ, antimicrobial resistance genes were located within two plasmids: a 28.6 kb lnu(A)-carrying plasmid (pCGMH_SL138) in CGMH-SL138 and a 26 kb plasmid carrying non-lnu(A) resistance genes (pCGMH_SL131) in CGMH-SL131. Both plasmids shared common genetic features with multiple copies of IS257 flanked by genes conferring resistance to aminoglycoside (aacA-aphD and aadD), TET (tetk), and cadmium (cadDX) and tolerance to chlorhexidine (qacA/R); however, only pCGMH_SL138 harbored lnu(A) that conferred resistance to lincomycin and rep13 that encodes a replication initiation protein. Unlike ST6-MRSL, none of the ST3-MRSL isolates contained the ermA gene. Instead, most isolates harbored lnu(A) (20/30, 66.7%), and several other resistance genes found on pCGMH_SL138. These isolates and transformants containing pCGMH_SL138 exhibited susceptibility to ERY and higher MICs for lincomycin and aforementioned antibiotics. A novel lnu(A)-carrying plasmid, pCGMH_SL138, that harbored a multiresistance gene cluster, was identified in ST3-MRSL strains and may contribute to the dissemination of antibiotic resistance in staphylococci.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Staphylococcus lugdunensis , Antibacterianos/farmacologia , Farmacorresistência Bacteriana , Humanos , Lincomicina , Resistência a Meticilina/genética , Testes de Sensibilidade Microbiana , Plasmídeos/genética , Infecções Estafilocócicas/tratamento farmacológico , Staphylococcus lugdunensis/genética
13.
Appl Microbiol Biotechnol ; 106(17): 5687-5699, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35906441

RESUMO

Antibiotic resistance genes are usually tightly controlled by transcription factors and RNA regulatory elements including sRNAs, riboswitches, and attenuators, and their expression is activated to respond to antibiotic exposure. In previous work, we revealed that the rppA gene is regulated by attenuator LRR and two mistranslation products in Bacillus thuringiensis BMB171. However, its function and promoter regulation is still not precise. In this study, we demonstrated that the encoding product of the rppA gene acts as an ARE1 ABC-F protein and confers resistance to antibiotics virginiamycin M1 and lincomycin when overexpressed. Besides the reported attenuator LRR, the expression of the rppA gene is controlled by the sigma factor SigA and a global transcription factor CcpA. Consequently, its promoter activity is mainly maintained at the stationary phase of cell growth and inhibited in the presence of glucose. Our study revealed the function and regulation of the rppA gene in detail. KEY POINTS: • The RppA protein acts as an ARE1 ABC-F protein • The rppA gene confers resistance to antibiotics virginiamycin M1 and lincomycin when overexpressed • The expression of the rppA gene is regulated by the sigma factor SigA and the pleiotropic regulator CcpA.


Assuntos
Bacillus thuringiensis , Antibacterianos , Proteínas de Bactérias , Resistência Microbiana a Medicamentos , Regulação Bacteriana da Expressão Gênica , Imunoglobulina A Secretora , Lincomicina , Fator sigma , Estreptogramina A , Fatores de Transcrição , Transcrição Genética
14.
Int J Mol Sci ; 23(11)2022 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-35682750

RESUMO

The adverse effects of short-term megadose of antibiotics exposure on the gastrointestinal and liver tissue reactions in young children have been reported. Antibiotic-induced intestinal and liver reactions are usually unpredictable and present a poorly understood pathogenesis. It is, therefore, necessary to develop strategies for reducing the adverse effects of antibiotics. Studies on the harm and rescue measures of antibiotics from the perspective of the gut-liver system are lacking. Here, we demonstrate that lincomycin exposure reduced body weight, disrupted the composition of gut microbiota and intestinal morphology, triggered immune-mediated injury and inflammation, caused liver dysfunction, and affected lipid metabolism. However, baicalin administration attenuated the lincomycin-induced changes. Transcriptome analysis showed that baicalin improved immunity in mice, as evidenced by the decreased levels of intestinal inflammatory cytokines and expression of genes that regulate Th1, Th2, and Th17 cell differentiation, and inhibited mucin type O-glycan biosynthesis pathways. In addition, baicalin improved liver function by upregulating the expression of genes involved in bile acid secretion and lipid degradation, and downregulating genes involved in lipid synthesis in lincomycin-treated mice. Bile acids can regulate intestinal immunity and strengthen hepatoenteric circulation. In addition, baicalin also improved anti-inflammatory bacteria abundance (Blautia and Coprobacillus) and reduced pathogenic bacteria abundance (Proteobacteria, Klebsiella, and Citrobacter) in lincomycin-treated mice. Thus, baicalin can ameliorate antibiotic-induced injury and its associated complications such as liver disease.


Assuntos
Inflamação , Lincomicina , Animais , Antibacterianos/efeitos adversos , Antibacterianos/metabolismo , Pré-Escolar , Flavonoides , Humanos , Inflamação/patologia , Lincomicina/metabolismo , Lincomicina/farmacologia , Lipídeos/farmacologia , Fígado/metabolismo , Camundongos , Camundongos Endogâmicos C57BL
15.
Plant Sci ; 320: 111265, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35643615

RESUMO

Chloroplast biogenesis requires a tight communication between nucleus and plastids. By retrograde signals, plastids transmit information about their functional and developmental state to adjust nuclear gene expression, accordingly. GENOMES UNCOUPLED 1 (GUN1), a chloroplast-localized protein integrating several developmental and stress-related signals, is one of the main players of retrograde signaling. Here, we focused on the interplay between GUN1 and redox regulation during biogenic retrograde signaling, by investigating redox parameters in Arabidopsis wild type and gun1 seedlings. Our data highlight that during biogenic retrograde signaling superoxide anion (O2-) and hydrogen peroxide (H2O2) play a different role in response to GUN1. Under physiological conditions, even in the absence of a visible phenotype, gun1 mutants show low activity of superoxide dismutase (SOD) and ascorbate peroxidase (APX), with an increase in O2- accumulation and lipid peroxidation, suggesting that GUN1 indirectly protects chloroplasts from oxidative damage. In wild type seedlings, perturbation of chloroplast development with lincomycin causes H2O2 accumulation, in parallel with the decrease of ROS-removal metabolites and enzymes. These redox changes do not take place in gun1 mutants which, in contrast, enhance SOD, APX and catalase activities. Our results indicate that in response to lincomycin, GUN1 is necessary for the H2O2-dependent oxidation of cellular environment, which might contribute to the redox-dependent plastid-to nucleus communication.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Proteínas de Ligação a DNA/metabolismo , Regulação da Expressão Gênica de Plantas , Peróxido de Hidrogênio/metabolismo , Lincomicina/metabolismo , Oxirredução , Plântula/genética , Superóxido Dismutase/metabolismo
16.
J Glob Antimicrob Resist ; 29: 360-370, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35533984

RESUMO

OBJECTIVES: Macrolides have a long history of use in animals and humans. Dynamics of macrolide-antibiotic resistance genes (ARGs) in waterways from the origin to the sea has not been reported. METHODS: Resistant bacterial rate was measured by culture method, and copy numbers of macrolide-ARGs, mef(A), erm(B), mph(B), mef(C)-mph(G), and mobile genetic elements (MGEs) traI and IntI1 were quantitated in environmental DNA. Community composition in each site was investigated by 16S rRNA gene metagenomic sequencing. In Yilan area, antibiotics were quantitated. RESULTS: Surface water samples from pig farms to the sea in southern and northern areas in Taiwan were monitored. Macrolide-resistant bacteria accounted for 3%-28% of total colony-forming bacteria in aquaculture ponds and rivers, whereas in pig farm wastewater it was 26%-100%. Three common macrolide-ARGs mef(A), erm(B), and mph(B) and the relatively new mef(C)-mph(G) were frequently detected in pig farms, but not in aquaculture ponds and the sea. Rivers receiving pig wastewater showed ARG contamination similar to the pig farms. Among the MGEs, IntI1 was frequently distributed in all sites and was positively related to mef(A), erm(B), and mph(B) but not to mef(C)-mph(G). CONCLUSION: Pig farms are the origin of macrolide-ARGs, although macrolide contamination is low. Since lincomycin was detected in pig farms in the northern area, the increase of macrolide-ARGs is a future concern due to cross-resistance to lincomycin. ARGs abundance in aquaculture ponds was low, though MGEs were detected. Relation of IntI1 to ARG suggests convergence of ARGs to specific MGEs might be time/history dependent.


Assuntos
Antibacterianos , Macrolídeos , Animais , Antibacterianos/farmacologia , Bactérias , Farmacorresistência Bacteriana/genética , Genes Bacterianos , Sequências Repetitivas Dispersas , Lincomicina , Macrolídeos/farmacologia , RNA Ribossômico 16S/genética , Suínos , Taiwan , /microbiologia
17.
Lett Appl Microbiol ; 75(4): 881-887, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35526150

RESUMO

Lactobacillus paracasei SLP 16 was obtained from liquor cellar mud, and it was analysed by genome sequencing on Illumina Hiseqq platform. Then the biological information of L. paracasei SLP16 was analysed by ExPasy (website), and the toxin safety of the strain SLP 16 was analysed by PSI/PHI in the virulence factor database VFDB. Through the second-generation DNA sequencing platform technology, the whole genome information of L. paracasei SLP16 was obtained, which showed that the genome size of the strain SLP 16 was 2·65 mol l-1 , and the GC content of the strain SLP 16 was 46·9%. And a total of 3131 genes were detected, including 3067 genes encoding protein and 63 genes encoding RNA. Whole genome analysis showed that L. paracasei SLP16 had five coding genes of F0 F1 -ATPase, four coding genes of Na+ /H+ antiporter and three coding genes of A-ATPase, which were closely related to the acid tolerance of lactic acid bacteria (LAB). Whole genome analysis of L. paracasei SLP16 showed that SLP 16 had only one CFA synthetic coding gene, and no important BSH coding gene; however, it had F0 F1 -ATPase, Na+ /H+ antiporter and several two-component regulatory systems, and which were related to bile salt tolerance of LAB. Safety evaluation in L. paracasei SLP16 showed that it did not have the virulence factor coding gene related to toxin. Common antibiotic sensitivity tests showed that L. paracasei SLP16 was resistant to compounds such as sulfamethoxazole, ciprofloxacin, gentamicin and lincomycin. In summary, L. paracasei SLP16 had coding genes closely related to acid tolerance and bile salt tolerance, and no coding gene of virulence factors related to toxins, and few kinds of resistant antibiotics. Therefore, whole genome analysis showed that L. paracasei SLP16 was a safe probiotic strain that can be safely applied.


Assuntos
Probióticos , Adenosina Trifosfatases/metabolismo , Antibacterianos/metabolismo , Antiporters , Ciprofloxacina , Genômica , Gentamicinas , Lincomicina/metabolismo , RNA/metabolismo , Sulfametoxazol , Fatores de Virulência/genética , Fatores de Virulência/metabolismo
18.
Avian Pathol ; 51(4): 374-380, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35616517

RESUMO

ABSTRACTMycoplasma iowae, a potential re-emerging avian pathogen mainly affecting turkeys, has been reported from many parts of the world. Poor hatchability, embryonic death, joint and skeletal abnormalities, poor ossification, runting-stunting, poor feathering and airsacculitis may be observed in infected flocks. The reduction of the severity of clinical signs and short-term control of M. iowae are performed by antibiotic treatment. However, M. iowae develops resistance more rapidly and is considered to be more resistant to antimicrobials than other avian pathogenic mycoplasmas. The aim of the present study was to determine the in vitro susceptibility of 101 M. iowae isolates and strains to ten clinically important antimicrobial agents, and to analyse and compare the susceptibility patterns of isolates of various origins and from a wide time-period. The examined reference strains showed high susceptibility to all antimicrobials except for spectinomycin. Low concentrations of tiamulin, florfenicol and oxytetracycline inhibited the growth of the clinical isolates. Nevertheless, slow tendency of increasing minimum inhibitory concentration (MIC) values was observed over time in the case of the above mentioned agents, while MIC values of enrofloxacin showed relatively rapid changes. Spiramycin, erythromycin, tilmicosin, tylosin, lincomycin and spectinomycin did not inhibit the bacterial growth in most of the cases. Isolates originating from captive game birds showed similar susceptibility profiles to isolates from industrial turkey hosts. The widely detected low susceptibility of M. iowae isolates to macrolides, lincomycin and spectinomycin, and the increase of MIC values of frequently used antimicrobials against this pathogen, emphasize the importance of targeted antibiotic therapy.RESEARCH HIGHLIGHTSAntimicrobial susceptibilities of 101 Mycoplasma iowae isolates were determined.Minimum inhibitory concentrations were determined by broth micro-dilution method.Tiamulin, oxytetracycline and florfenicol showed low MIC values.Isolates rapidly adapted to antimicrobial pressure.


Assuntos
Anti-Infecciosos , Infecções por Mycoplasma , Mycoplasma iowae , Oxitetraciclina , Doenças das Aves Domésticas , Animais , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Anti-Infecciosos/farmacologia , Lincomicina/farmacologia , Lincomicina/uso terapêutico , Testes de Sensibilidade Microbiana/veterinária , Infecções por Mycoplasma/microbiologia , Infecções por Mycoplasma/veterinária , Oxitetraciclina/farmacologia , Oxitetraciclina/uso terapêutico , Doenças das Aves Domésticas/tratamento farmacológico , Espectinomicina/farmacologia , Espectinomicina/uso terapêutico
20.
J Appl Microbiol ; 133(2): 400-409, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35384192

RESUMO

AIMS: Assessing the role of ramRsl , a gene absent in a lincomycin over-producing strain, in the regulation of morphological development and lincomycin biosynthesis in Streptomyces lincolnensis. METHODS AND RESULTS: The gene ramRsl was deleted from the wild-type strain NRRL 2936 and the ΔramR mutant strain was characterized by a slower growth rate and a delayed morphological differentiation compared to the original strain NRRL 2936. Furthermore, the ΔramR produced 2.6-fold more lincomycin than the original strain, and consistently the level of expression of all lincomycin cluster located genes was enhanced at 48 and 96 h in the ΔramR. Complementation of ΔramR with an intact copy of ramRsl restored all wild-type features, whereas the over-expression of ramRsl led to a reduction of 33% of the lincomycin yield. Furthermore, the level of expression of glnR, bldA and SLCG_2919, three of known lincomycin biosynthesis regulators, was lower in the ΔramR than in the original strain at the early stage of fermentation and we demonstrated, using electrophoretic mobility shift assay and XylE reporter assay, that glnR is a novel direct target of RamR. CONCLUSIONS: Altogether, these results indicated that, beyond promoting the morphological development, RamR regulates negatively lincomycin biosynthesis and positively the expression of the nitrogen regulator GlnR. SIGNIFICANCE AND IMPACT OF THE STUDY: We demonstrated that RamR plays a negative role in the regulation of lincomycin biosynthesis in S. lincolnensis. Interestingly, the deletion of this gene in other antibiotic-producing Streptomyces strains might also increase their antibiotic-producing abilities.


Assuntos
Regulação Bacteriana da Expressão Gênica , Streptomyces , Antibacterianos/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Lincomicina/metabolismo , Streptomyces/genética , Streptomyces/metabolismo
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