Abstract:
:The alternative sigma factor sigma54 has been implicated in diverse functions within the cells. In this study, we have constructed an rpoN mutant of Pseudomonas aeruginosa and investigated its importance as a target for antimicrobial agents, such as quinolones and carbapenems. The stationary-phase cells of the rpoN mutant displayed a survival rate approximately 15 times higher than that of the wild-type cells in the presence of quinolones and carbapenems. The stationary phase led to substantial production of pyoverdine by the P. aeruginosa rpoN mutant. Pyoverdine synthesis correlated with decreased susceptibility to antimicrobial agents. Quantitative real-time PCR revealed that stationary-phase cells of the rpoN mutant grown without an antimicrobial agent had approximately 4- to 140- and 2- to 14-fold-higher levels of transcripts of the pvdS and vqsR genes, respectively, than the wild-type strain. In the presence of an antimicrobial agent, levels of pvdS and vqsR transcripts were elevated 400- and 5-fold, respectively, in comparison to the wild-type levels. Flow cytometry assays using a green fluorescent protein reporter demonstrated increased expression of the vqsR gene in the rpoN mutant throughout growth. A pvdS mutant of P. aeruginosa, deficient in pyoverdine production, was shown to be susceptible to biapenem. These findings suggest that rpoN is involved in tolerance to antimicrobial agents in P. aeruginosa and that its tolerant effect is partly dependent on increased pyoverdine production and vqsR gene expression.
journal_name
Antimicrob Agents Chemotherjournal_title
Antimicrobial agents and chemotherapyauthors
Viducic D,Ono T,Murakami K,Katakami M,Susilowati H,Miyake Ydoi
10.1128/AAC.00348-06subject
Has Abstractpub_date
2007-04-01 00:00:00pages
1455-62issue
4eissn
0066-4804issn
1098-6596pii
AAC.00348-06journal_volume
51pub_type
杂志文章abstract::Pseudomonas aeruginosa is equipped with the Sec and Tat protein secretion systems, which translocate the xenobiotic transporter MexAB-OprM and the pathogenic factor phospholipase C (PlcH), respectively. When the signal sequence of MexA was replaced with that of PlcH, the hybrid protein was successfully expressed and r...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.01495-09
更新日期:2010-04-01 00:00:00
abstract::Catheter-associated urinary tract infections (CAUTIs) constitute the majority of nosocomial urinary tract infections (UTIs) and pose significant clinical challenges. These infections are polymicrobial in nature and are often associated with multidrug-resistant pathogens, including uropathogenic Escherichia coli (UPEC)...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.00447-12
更新日期:2012-09-01 00:00:00
abstract::The Carba NP test was evaluated against a panel of 244 carbapenemase- and non-carbapenemase-producing Enterobacteriaceae and Pseudomonas aeruginosa isolates. We confirmed the 100% specificity and positive predictive value of the test, but the sensitivity and negative predictive value were 72.5% and 69.2%, respectively...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.00878-13
更新日期:2013-09-01 00:00:00
abstract::Pyrosequencing was used to detect rapidly and estimate the number of 23S rRNA genes with a G2576T mutation in 43 linezolid-resistant and -susceptible clinical isolates of enterococci. The method showed 100% concordance with PCR-restriction fragment length polymorphism for detecting isolates homozygous for either G2576...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/aac.47.11.3620-3622.2003
更新日期:2003-11-01 00:00:00
abstract::Passive antibody administration is a potentially useful approach for the therapy of human Cryptococcus neoformans infections. To evaluate the efficacy of the human immunoglobulin G1 (IgG1) constant region against C. neoformans and to construct murine antibody derivatives with reduced immunogenicities and longer half-l...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/aac.38.7.1507
更新日期:1994-07-01 00:00:00
abstract::While the inflammatory response to severe pneumonia is paramount in limiting and resolving the infection, excessive inflammation can lead to deleterious effects. We theorized that patients with severe community-acquired pneumonia (CAP) who were treated with macrolides and aspirin would receive benefit beyond that of c...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章,多中心研究
doi:10.1128/AAC.01556-18
更新日期:2019-01-29 00:00:00
abstract::After vaginal insertion of a 300-mg ovule of tioconazole in 10 patients with vaginal candidiasis, the mean concentration in plasma was 21.2 ng/ml (range, 10.6 to 35.8 ng/ml) at 8 h and was not measurable at 24 h in 9 of 10 patients. The mean vaginal concentration at 24 h was 21.4 mg/liter (range, 2.4 to 50 mg/liter) a...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/aac.27.6.964
更新日期:1985-06-01 00:00:00
abstract::Acute kidney injury (AKI) occurs in a substantial proportion of critically ill patients receiving intravenous colistin. In the pharmacokinetic/toxicodynamic analysis reported here, the relationship of the occurrence of AKI to exposure to colistin and a number of potential patient factors was explored in 153 critically...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章,多中心研究
doi:10.1128/AAC.01367-17
更新日期:2017-10-24 00:00:00
abstract::Anidulafungin concentrations were quantified with high-pressure liquid chromatography (HPLC) and UV detection of the ascites fluid and pleural effusion of 10 adult critically ill patients. Samples were collected from ascites fluid and from pleural drains or during paracentesis and thoracentesis, respectively. Anidulaf...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.02326-17
更新日期:2018-03-27 00:00:00
abstract::The management of long-term central venous catheter (LTCVC) infections by multidrug-resistant (MDR) bacteria in cancer patient is a challenge. The objectives of this study were to analyze outcomes in cancer patients with LTCVC-associated infection, identify risks for unfavorable outcomes, and determine the impact of M...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.00569-18
更新日期:2018-08-27 00:00:00
abstract::Defensins are small cationic bactericidal peptides present abundantly in the granules of polymorphonuclear neutrophils (PMNs). Human PMNs contain four defensins termed HNP-1 to HNP-4. We used a new assay system in agar plates, the radial diffusion assay, to evaluate the effects of human defensins against gram-positive...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.40.10.2280
更新日期:1996-10-01 00:00:00
abstract::The in vitro susceptibility of 409 clinical isolates to HR 810, a new cephalosporin, was evaluated and compared with their susceptibility to aztreonam, cefazolin, ceftazidime, imipenem, moxalactam, piperacillin, and gentamicin. On a weight basis, the activity of HR 810 against gram-negative bacilli was equivalent or s...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/aac.26.2.277
更新日期:1984-08-01 00:00:00
abstract::The in vitro activities of magainin analogs against Blastocystis hominis, Entamoeba histolytica, and Trypanosoma cruzi were assessed by protozoan morphological integrity and motility. The antiprotozoan activities in descending order were magainin B greater than G greater than H, the same order as the alpha-helix conte...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/aac.34.9.1824
更新日期:1990-09-01 00:00:00
abstract::The effect of antichagasic benznidazole (BZL; 100 mg/kg body weight/day, 3 consecutive days, intraperitoneally) on biotransformation systems and ABC transporters was evaluated in rats. Expression of cytochrome P-450 (CYP3A), UDP-glucuronosyltransferase (UGT1A), glutathione S-transferases (alpha glutathione S-transfera...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.02531-12
更新日期:2013-10-01 00:00:00
abstract::Aminoglycoside 2″-phosphotransferases are the major aminoglycoside-modifying enzymes in clinical isolates of enterococci and staphylococci. We describe a novel aminoglycoside 2″-phosphotransferase from the Gram-negative pathogen Campylobacter jejuni, which shares 78% amino acid sequence identity with the APH(2″)-Ia do...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.02049-12
更新日期:2013-01-01 00:00:00
abstract::We performed the characterization of a multidrug-resistant (MDR) Enterobacter spp. isolate highlighting the genetic aspects of the antimicrobial resistance genes. An Enterobacter spp. isolate (Ec61) was recovered in 2014 from a transtracheal aspirate sample from a patient admitted to a Brazilian tertiary hospital and ...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.01193-20
更新日期:2020-12-14 00:00:00
abstract::Daptomycin is a lipopeptide antibiotic with potent in vitro activity against gram-positive cocci, including Staphylococcus aureus. This study evaluated the in vitro and in vivo efficacies of daptomycin against two clinical isolates: methicillin-resistant S. aureus (MRSA) 277 (vancomycin MIC, 2 microg/ml) and glycopept...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.00510-07
更新日期:2008-07-01 00:00:00
abstract::The sterol 14-demethylase P450 (CYP51) of a fluconazole-resistant isolate of Candida albicans, DUMC136, showed reduced susceptibility to this azole but with little change in its catalytic activity. Twelve nucleotide substitutions, resulting in four amino acid changes, were identified in the DUMC136 CYP51 gene in compa...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.43.5.1163
更新日期:1999-05-01 00:00:00
abstract::The pharmacodynamic effects of metronidazole on Trichomonas vaginalis have been poorly characterized. The present in vitro study was performed to characterize the relationship between killing of trichomonads and metronidazole exposure (metronidazole concentration and time of exposure). Five laboratory strains and five...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/aac.39.8.1848
更新日期:1995-08-01 00:00:00
abstract::Since beta-lactam antibiotics have concentration-independent killing, bacterial eradication is a function of the time the serum drug concentration remains above the drug's MIC (T > MIC). We compared the serum bactericidal titers (SBTs) of ceftazidime given by continuous infusion (CI) or by intermittent bolus dosing (B...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 临床试验,杂志文章,随机对照试验
doi:10.1128/AAC.40.1.61
更新日期:1996-01-01 00:00:00
abstract::We compared the activity of delavirdine (DLV) plus zidovudine (AZT) (n = 300) with that of AZT (n = 297) against human immunodeficiency virus type 1 in a randomized, double-blind, placebo-controlled trial. DLV exerted a transient antiviral effect, and mutations for resistance to DLV were found in more than 90% of subj...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 临床试验,杂志文章,随机对照试验
doi:10.1128/aac.44.11.3155-3157.2000
更新日期:2000-11-01 00:00:00
abstract::A structurally diverse library of 93 lipophilic di- and tricyclic diaminopyrimidine derivatives was tested for the ability to inhibit recombinant dihydrofolate reductase (DHFR) cloned from human and bovine isolates of Cryptosporidium parvum (J. R. Vásquez et al., Mol. Biochem. Parasitol. 79:153-165, 1996). In parallel...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.45.12.3293-3303.2001
更新日期:2001-12-01 00:00:00
abstract::Antibiotic-impregnated beads are used in the dead bone space following debridement surgery to deliver local, high concentrations of antibiotics. Polymethylmethacrylate (PMMA), 2,000-molecular-weight (MW) polylactic acid (PLA), Poly(DL-lactide)-coglycolide (PL:CG; 90:10, 80:20, and 70:30), and the combination 2,000-MW ...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.41.2.415
更新日期:1997-02-01 00:00:00
abstract::The minimal inhibitory concentration of temocillin (BRL 17421) against 476 clinical isolates was determined by an agar dilution method. Temocillin was active against most of the Enterobacteriaceae, Haemophilus, and Neisseria strains tested. The compound showed low activity or was inactive against Bacteroides, Campylob...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/aac.22.4.535
更新日期:1982-10-01 00:00:00
abstract::Zika virus (ZIKV), a flavivirus transmitted by mosquitoes, was an almost neglected pathogen until its introduction in the Americas in 2015 and its subsequent explosive spread throughout the continent, where it has infected millions of people. The virus has caused social and sanitary alarm, mainly due to its associatio...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章,评审
doi:10.1128/AAC.00411-17
更新日期:2017-05-24 00:00:00
abstract::This study explored metronidazole and hydroxymetronidazole distribution in the cerebrospinal fluid (CSF) of brain-injured patients. Four brain-injured patients with external ventricular drain received 500 mg of metronidazole over 0.5 h every 8 h. CSF and blood samples were collected at steady state over 8 h, and the m...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.01762-13
更新日期:2014-01-01 00:00:00
abstract::PD 131628 is a new aminopyrrolidine-substituted fluorocyclopropyl naphthyridine quinolone which possesses high in vitro activity against a wide spectrum of bacterial species. The MICs for greater than or equal to 90% of strains were 0.125 to 0.25 microgram/ml for staphylococci, Streptococcus pyogenes, and S. pneumonia...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/aac.35.1.141
更新日期:1991-01-01 00:00:00
abstract::Tuberculosis (TB) treatment is long and requires multiple drugs, likely due to various phenotypes of TB bacilli with variable drug susceptibilities. Drugs with broad activity are urgently needed. This study aimed to evaluate delamanid's activity against growing or dormant bacilli in vitro as well as in vivo Cultures o...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.02402-16
更新日期:2017-05-24 00:00:00
abstract::TEM-24 remains one of the most widespread TEM-type extended-spectrum beta-lactamases (ESBLs) among Enterobacteriaceae. To analyze the reasons influencing its spread and persistence, a multilevel population genetics study was carried out on 28 representative TEM-24 producers from Belgium, France, Portugal, and Spain (1...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.00959-09
更新日期:2010-02-01 00:00:00
abstract::Two TolC homologs, PM0527 and PM1980, were identified for Pasteurella multocida. A pm0527 mutant displayed increased susceptibility to a range of chemicals, including rifampin (512-fold) and acridine orange (128-fold). A pm1980 mutant showed increased susceptibility to rifampin, ceftazidime, and vancomycin. ...
journal_title:Antimicrobial agents and chemotherapy
pub_type: 杂志文章
doi:10.1128/AAC.00245-08
更新日期:2008-11-01 00:00:00