Phosphate regulon in members of the family Enterobacteriaceae: comparison of the phoB-phoR operons of Escherichia coli, Shigella dysenteriae, and Klebsiella pneumoniae.

ABSTRACT Although resistance to the expanded-spectrum cephalosporins among members of the family Enterobacteriaceae lacking inducible β-lactamases occurs virtually worldwide, little is known about this problem among isolates recovered in South Africa. Isolates of Klebsiella pneumoniae, Escherichia coli, and Proteus mirabilis resistant to expanded-spectrum cephalosporins recovered from patients in various parts of South Africa over a 3-month period were investigated for extended-spectrum β-lactamase production. Antibiotic susceptibility was determined by standard disk diffusion and agar dilution procedures. Production of extended-spectrum β-lactamases was evaluated by using the double-disk test, and the β-lactamases were characterized by spectrophotometric hydrolysis assays and an isoelectric focusing overlay technique which simultaneously determined isoelectric points and general substrate or inhibitor characteristics. DNA amplification and sequencing were performed to confirm the identities of these enzymes. The P. mirabilis and E. coliisolates were found to produce TEM-26-type, SHV-2, and SHV-5 extended-spectrum β-lactamases. An AmpC-related enzyme which had a pI of 8.0 and which conferred resistance to cefoxitin as well as the expanded-spectrum cephalosporins was found in a strain of K. pneumoniae. This is the first study which has identified organisms producing different extended-spectrum β-lactamases from South Africa and the first report describing strains of P. mirabilis producing a TEM-26-type enzyme. The variety of extended-spectrum β-lactamases found among members of the familyEnterobacteriaceae isolated from major medical centers in South Africa is troubling and adds to the growing list of countries where these enzymes pose a serious problem for antimicrobial therapy.

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High Prevalence of Plasmid-Mediated Quinolone Resistance Determinants qnr, aac(6′)-Ib-cr, and qepA among Ceftiofur-Resistant Enterobacteriaceae Isolates from Companion and Food-Producing Animals

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00886-08 ◽

2008 ◽

Vol 53 (2) ◽

pp. 519-524 ◽

Cited By ~ 134

Author(s):

Junying Ma ◽

Zhenling Zeng ◽

Zhangliu Chen ◽

Xiaogang Xu ◽

Xiaoying Wang ◽

...

Keyword(s):

Escherichia Coli ◽

Klebsiella Pneumoniae ◽

Companion Animals ◽

Pcr Amplification ◽

Guangdong Province ◽

Quinolone Resistance ◽

Resistance Determinants ◽

The Family ◽

High Prevalence ◽

Few Data

ABSTRACT Three kinds of plasmid-mediated quinolone resistance (PMQR) determinants have been discovered and have been shown to be widely distributed among clinical isolates: qnr genes, aac(6′)-Ib-cr, and qepA. Few data on the prevalence of these determinants in strains from animals are available. The presence of PMQR genes in isolates from animals was determined by PCR amplification and DNA sequencing. The production of extended-spectrum β-lactamases (ESBLs) and AmpC β-lactamases in the strains was detected, and their genotypes were determined. The genetic environment of PMQR determinants in selected plasmids was analyzed. All samples of ceftiofur-resistant (MICs ≥ 8 μg/ml) isolates of the family Enterobacteriaceae were selected from 36 companion animals and 65 food-producing animals in Guangdong Province, China, between November 2003 and April 2007, including 89 Escherichia coli isolates, 9 Klebsiella pneumoniae isolates, and isolates of three other genera. A total of 68.3% (69/101) of the isolates produced ESBLs and/or AmpC β-lactamases, mainly those of the CTX-M and CMY types. Of the 101 strains, PMQR determinants were present in 35 (34.7%) isolates, with qnr, aac(6′)-Ib-cr, and qepA detected alone or in combination in 8 (7.9%), 19 (18.8%), and 16 (15.8%) strains, respectively. The qnr genes detected included one qnrB4 gene, four qnrB6 genes, and three qnrS1 genes. Five strains were positive for both aac(6′)-Ib-cr and qepA, while one strain was positive for qnrS1, aac(6′)-Ib-cr, and qepA. qnrB6 was flanked by two copies of ISCR1 with an intervening dfr gene downstream and sul1 and qacEΔ1 genes upstream. In another plasmid, aac(6′)-Ib-cr followed intI1 and arr-3 was downstream. PMQR determinants are highly prevalent in ceftiofur-resistant Enterobacteriaceae strains isolated from animals in China. This is the first report of the occurrence of PMQR determinants among isolates from companion animals.

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Ceftazidime-Resistant EnterobacteriaceaeIsolates from Three Polish Hospitals: Identification of Three Novel TEM- and SHV-5-Type Extended-Spectrum β-Lactamases

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.42.3.514 ◽

1998 ◽

Vol 42 (3) ◽

pp. 514-520 ◽

Cited By ~ 53

Author(s):

Marek Gniadkowski ◽

Ines Schneider ◽

Renate Jungwirth ◽

Waleria Hryniewicz ◽

Adolf Bauernfeind

Keyword(s):

Escherichia Coli ◽

Amino Acid ◽

Klebsiella Pneumoniae ◽

Detailed Analysis ◽

Amino Acid Substitutions ◽

New Combinations ◽

Extended Spectrum ◽

The Family ◽

Genetic Events ◽

Esbl Producers

ABSTRACT Twelve ceftazidime-resistant isolates of the familyEnterobacteriaceae (11 Klebsiella pneumoniaeisolates and 1 Escherichia coli isolate) were collected in 1995 from three Polish hospitals located in different cities. All were identified as producers of extended-spectrum β-lactamases (ESBLs). Detailed analysis of their β-lactamase contents revealed that six of them expressed SHV-5-like ESBLs. The remaining six were found to produce three different TEM enzymes, each characterized by a pI value of 6.0 and specified by new combinations of amino acid substitutions. The amino acid substitutions compared to the TEM-1 β-lactamase sequence were Gly238Ser, Glu240Lys, and Thr265Met for TEM-47; Leu21Phe, Gly238Ser, Glu240Lys, and Thr265Met for TEM-48; and Leu21Phe, Gly238Ser, Glu240Lys, Thr265Met, and Ser268Gly for TEM-49. The new TEM β-lactamases, TEM-47, TEM-48, and TEM-49, belong to a subfamily of TEM-2-related enzymes. Genes coding for TEM-47 and TEM-49 could have originated from the TEM-48-encoding sequence by various single genetic events. The new TEM derivatives probably document the already advanced microevolution of ESBLs ongoing in Polish hospitals, in a majority of which no monitoring of ESBL producers was performed before 1996.

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Evaluación antibacteriana y perfil cromatográfico (CG-EM) de fracciones de hojas y tallo de Calotropis procera (Linn).

FACSALUD-UNEMI ◽

10.29076/issn.2602-8360vol2iss2.2018pp19-25p ◽

2018 ◽

Vol 2 (2) ◽

pp. 19-25

Author(s):

Asoso Oluwakemi-Sola ◽

Oladunmoye Muftau-Kolawole ◽

Ogundare Ayodele Oluyemisi

Keyword(s):

Escherichia Coli ◽

Klebsiella Pneumoniae ◽

Salmonella Typhi ◽

Shigella Dysenteriae ◽

Calotropis Procera ◽

E Coli

La medicina tradicional, también conocida como medicina ancestral o popular, comprende sistemas de conocimientos que se desarrollaron a lo largo de generaciones dentro de varias sociedades antes de la era de la medicina moderna. La cromatografía en columna fue utilizada para recolectar fracciones crudas; se utilizaron disolventes como éter de petróleo, cloroformo y metanol. Las actividades antibacterianas de las fracciones crudas de Calotropis procera (hojas y tallo) se evaluaron en este estudio, utilizando algunos microorganismos seleccionados como Escherichia coli, Shigella dysenteriae ATCC 24162, Salmonella typhi y Klebsiella pneumoniae ATCC 34089; para tal fin, la planta fue extraída usando acetona y metanol acuoso. El método de difusión en disco de papel fue usado después de que la zona de inhibición alrededor de los discos fue estimada. Los resultados mostraron que en las hojas de la planta, E. coli con la fracción acuoso-metanol y K. pneumoniae ATCC 34089 con la fracción del éter de petróleo-acetona, tuvieron el rendimiento más alto de 30mm respectivamente; mientras que en el tallo, K. pneumoniae ATCC 34089 con la fracción del metanol-metanol tuvo el rendimiento más alto de 25mm. La elucidación estructural de los compuestos bioactivos en los extractos fue evaluada usando CG-EM, identificándose compuestos químicos como fenol, palmitato metílico, ácido ftálico, ácido 9-octadecenoico y otros compuestos conocidos como antimicrobianos valiosos, con actividades biológicas y propiedades antioxidantes. Las hojas y el tallo han presentado buenos compuestos químicos, que pueden ser responsables del efecto antimicrobiano observado.

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Štúidium rastu a produkcie biogénnych amínov niektorými mikroorganizmami za modelových podmienok

Czech Journal of Food Sciences ◽

10.17221/10015-cjfs ◽

1999 ◽

Vol 17 (No. 1) ◽

pp. 15-21 ◽

Cited By ~ 5

Author(s):

G. Greif ◽

M. Greifova ◽

J. Dvoran ◽

J. Karovicova ◽

V. Buchtova

Keyword(s):

Escherichia Coli ◽

Growth Rate ◽

Klebsiella Pneumoniae ◽

Specific Growth ◽

Growth Curves ◽

Enterobacter Aerogenes ◽

Lag Phase ◽

E Coli ◽

The Family ◽

Cell Densities

The study was aimed at the growth of selected strains from the family Enterobacteriaceae (Escherichia coli, Enterobacter aerogenes and Klebsiella pneumoniae) in meat-peptone (MPB) broth and cabbage juice at different cultivation temperatures, and at the production of biogenic amines (cadaverine, putrescine, histamine). Bacterial growth was evaluated on the basis of specific growth rate (IJm) and lag phase (A.) calculated from growth curves. Cadaverine was produced as the first amine in MPB and cabbage juice by all studied st rains at the cultivation temperatures and at Jiving cell densities 10 6 KTJ/cm3. Putrescine was produced by E. coli only in both substrates at the cultivation temperatures. Histamine was produced by E. coli at 18 °C in cabbage juice and by Enterobacter aerogenes in both substrates at the cultivation temperatures.

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Monitoreo microbiológico para la gestión ambiental de Aguas Residuales Hospitalarias

Ciencia Digital ◽

10.33262/cienciadigital.v3i3.4..882 ◽

2019 ◽

Vol 3 (3.4.) ◽

pp. 342-353

Author(s):

Andrés Beltrán Dávalos ◽

Mayra Escudero Vilema ◽

Silvana Córdova Morales ◽

Carlos Rolando Rosero Erazo

Keyword(s):

Escherichia Coli ◽

Staphylococcus Aureus ◽

Klebsiella Pneumoniae ◽

Enterobacter Cloacae ◽

Shigella Dysenteriae ◽

Salmonella Spp

El estudio microbiológico para evaluar patógenos en aguas residuales de la unidad Hospitalaria General Puyo se desarrolló en los laboratorios de análisis bioquímicos y bacteriológicos de la Facultad de Ciencias de la Escuela Superior Politécnica de Chimborazo. Durante tres meses se recolectó 6 muestras compuestas con sus respectivas réplicas antes y después de la Planta de tratamiento de Aguas Residuales (PTAR) realizando análisis físico – químico como: pH, Conductividad, salinidad, sólidos disueltos totales, turbiedad, color, DBO5, DQO, seguido de un análisis microbiológico mediante siembras de vertido en placa para la identificación y cuantificación de bacterias: Escherichia Coli, Staphylococcus aureus y Salmonellas spp .y finalmente se realizó la Tinción Gram previo a realizar las pruebas bioquímicas donde se identificaron una totalidad de Bacilos Gram negativos, las bacterias identificadas fueron de la familia Enterobacteriaceae. Identificando las siguientes familias, Escherichia coli, (50%), Klebsiella pneumoniae, (10%) Enterobacter cloacae (0,1%) Shigella dysenteriae, (10%) Salmonella spp (30 %), concluyendo así que las aguas residuales provenientes de esta unidad Hospitalaria tienen un porcentaje de toxicidad alta y los tratamientos convencionales de aguas residuales no eliminan la su toxicidad biológica

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Occurrence of Extended-Spectrum β-Lactamases in Members of the Family Enterobacteriaceae in Italy: Implications for Resistance to β-Lactams and Other Antimicrobial Drugs

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.46.1.196-202.2002 ◽

2002 ◽

Vol 46 (1) ◽

pp. 196-202 ◽

Cited By ~ 94

Author(s):

T. Spanu ◽

F. Luzzaro ◽

M. Perilli ◽

G. Amicosante ◽

A. Toniolo ◽

...

Keyword(s):

Escherichia Coli ◽

Klebsiella Pneumoniae ◽

Synergistic Effect ◽

Blot Hybridization ◽

Nationwide Survey ◽

Antimicrobial Drugs ◽

Extended Spectrum ◽

The Family ◽

Amoxicillin Clavulanic Acid

ABSTRACT An Italian nationwide survey was carried out to assess the prevalences and the antimicrobial susceptibilities of members of the family Enterobacteriaceae producing extended-spectrum β-lactamases (ESBLs). Over a 6-month period, 8,015 isolates were obtained from hospitalized patients and screened for resistance to extended-spectrum cephalosporins and monobactams. On the basis of a synergistic effect between clavulanate and selected β-lactams (ceftazidime, aztreonam, cefotaxime, cefepime, and ceftriaxone), 509 isolates were found to be ESBL positive (6.3%). Colony blot hybridization with bla TEM and bla SHV DNA probes allowed one to distinguish four different genotypes: TEM-positive, SHV-positive, TEM- and SHV-positive, and non-TEM, non-SHV ESBL types. MICs for each isolate (E-test) were obtained for widely used β-lactams, combinations of β-lactams with β-lactamase inhibitors, aminoglycosides, and fluoroquinolones. Among ESBL-positive strains, Klebsiella pneumoniae, Proteus mirabilis, and Escherichia coli accounted for 73.6% of isolates. Overall, TEM-type ESBLs were more prevalent than SHV-type enzymes (234 versus 173), whereas the prevalence of strains producing both TEM- and SHV-type ESBLs was similar to that of isolates producing non-TEM, non-SHV enzymes (55 and 38, respectively). In vitro, all but one of the ESBL-producing isolates remained susceptible to imipenem. Susceptibility to other drugs varied: piperacillin-tazobactam, 91%; amoxicillin-clavulanic acid, 85%; cefoxitin, 78%; amikacin, 76%; ampicillin-sulbactam, 61%; ciprofloxacin, 58%; and gentamicin, 56%. Associated resistance to aminoglycosides and ciprofloxacin was observed most frequently among TEM-positive strains. Since therapeutic options for multiresistant Enterobacteriaceae are limited, combinations of β-lactams and β-lactamase inhibitors appear to represent an important alternative for treating infections caused by ESBL-producing Enterobacteriaceae.

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PENGUJIAN AKTIVITAS ANTIMIKROBA EKSTRAK ETIL ASETAT DAN METANOL KAYU RANTING SENGON (Falcataria moluccana) SAKIT

Journal of Indonesian Medical Laboratory and Science (JoIMedLabS) ◽

10.53699/joimedlabs.v2i1.23 ◽

2021 ◽

Vol 2 (1) ◽

pp. 55-67

Author(s):

Popy Listiani ◽

Popy Hasanah ◽

Alfi Rumidatul ◽

Feldha Fadhila ◽

Yayan Maryana

Keyword(s):

Escherichia Coli ◽

Candida Albicans ◽

Klebsiella Pneumoniae ◽

Salmonella Typhi ◽

Shigella Dysenteriae ◽

E Coli

Klebsiella pneumoniae, Shigella dysenteriae, Salmonella typhi, Escherichia coli, dan Candida albicans merupakan mikroorganisme yang paling sering menginfeksi di Indonesia. Penyakit infeksi dapat disembuhkan serta diminimalkan penularannya menggunakan antibiotik. Upaya pencarian senyawa antimikroba dari alam diharapkan mampu mengurangi pengaruh negatif antibiotik. Tanaman yang diduga memiliki kandungan antimikroba salah satunya pohon sengon. Penelitian ini bertujuan untuk mengetahui kemampuan ekstrak kayu ranting sengon (Falcataria moluccana) yang terinfeksi jamur U. tepperianum dengan pelarut etil asetat dan metanol sebagai antimikroba. Metode pengujian yang digunakan Kirby bauer dengan perlakuan 9%, 9.5%, 10%, 10.5%, dan 11%. Hasil penelitian ekstrak etil asetat kayu ranting sengon sakit menunjukkan adanya aktivitas antimikroba terhadap S. dysenteriae pada semua konsentrasi dan K. pneumoniae pada konsentrasi 11%, tidak ada aktivitas antimikroba terhadap E. coli. Ekstrak metanol kayu ranting sengon sakit menunjukkan adanya aktivitas antimikroba terhadap K. pneumoniae pada konsentrasi 10%, 10.5%, 11%, dan C. albicans pada semua konsentrasi, namun tidak menunjukkan aktivitas antimikroba terhadap E. coli, S. typhi, dan S. dysenteriae. Dapat disimpulkan bahwa ekstrak etil asetat kayu ranting sengon sakit dapat menghambat pertumbuhan S. dysenteriae dan K. pneumoniae. Ekstrak metanol kayu ranting sengon sakit dapat menghambat pertumbuhan K. pneumoniae dan C. albicans.

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