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1.
Org Lett ; 25(23): 4400-4405, 2023 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-37284758

RESUMO

Herein, we report the first total synthesis of the trisaccharide and tetrasaccharide repeating units of P. penneri 26 and P. vulgaris TG155, respectively, having a common disaccharide unit, 3-α-l-QuipNAc-(1 → 3)-α-d-GlcpNAc-(1 →. Striking features of the targets are the presence of rare sugar units, l-quinovosamine and l-rhamnosamine, all joined through α-glycosidic linkages. Major challenges in the formation of 1,2-cis glycosidic linkages in the case of d-glucosamine, l-quinovosamine, and d-galactosamine have been addressed.


Assuntos
Proteus penneri , Proteus vulgaris , Sequência de Carboidratos , Antígenos O , Dissacarídeos
2.
Int J Biol Macromol ; 163: 1168-1174, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32652158

RESUMO

The serological classification scheme of the opportunistic Proteus bacilli includes a number of Proteus penneri strains. The tested P. penneri 4034-85 strain turned out to be serologically distinguished in ELISA and Western blotting. The O-polysaccharide was obtained by mild acid degradation of the lipopolysaccharide of this strain and studied by sugar and methylation analyses and dephosphorylation along with 1H and 13C NMR spectroscopy, including 2D 1H,1H COSY, TOCSY, ROESY, 1H,13C HSQC, HMBC, and HSQC-TOCSY experiments, The O-polysaccharide was found to have a linear repeating unit containing glycerol 1-phosphate and two residues each of Gal and GlcNAc. The following O-polysaccharide structure was established, which, to our knowledge, is unique among known bacterial polysaccharide structures.


Assuntos
Antígenos O/química , Polissacarídeos Bacterianos/química , Proteus penneri/química , Proteus penneri/classificação , Sorogrupo , Ensaio de Imunoadsorção Enzimática , Humanos , Espectrometria de Massas , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Antígenos O/imunologia , Fosforilação , Proteus penneri/imunologia
3.
Nat Commun ; 11(1): 2730, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32483187

RESUMO

Bacteria have evolved sophisticated adaptive immune systems, called CRISPR-Cas, that provide sequence-specific protection against phage infection. In turn, phages have evolved a broad spectrum of anti-CRISPRs that suppress these immune systems. Here we report structures of anti-CRISPR protein IF9 (AcrIF9) in complex with the type I-F CRISPR RNA-guided surveillance complex (Csy). In addition to sterically blocking the hybridization of complementary dsDNA to the CRISPR RNA, our results show that AcrIF9 binding also promotes non-sequence-specific engagement with dsDNA, potentially sequestering the complex from target DNA. These findings highlight the versatility of anti-CRISPR mechanisms utilized by phages to suppress CRISPR-mediated immune systems.


Assuntos
Bactérias/metabolismo , Bacteriófagos/metabolismo , Sistemas CRISPR-Cas , DNA/metabolismo , RNA Guia de Cinetoplastídeos/metabolismo , Proteínas Virais/metabolismo , Sequência de Aminoácidos , Bactérias/genética , Bactérias/virologia , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Bacteriófagos/genética , Microscopia Crioeletrônica , DNA/química , DNA/genética , Modelos Moleculares , Complexos Multiproteicos/química , Complexos Multiproteicos/metabolismo , Complexos Multiproteicos/ultraestrutura , Conformação de Ácido Nucleico , Ligação Proteica , Conformação Proteica , Proteus penneri/genética , Proteus penneri/metabolismo , Proteus penneri/virologia , RNA Guia de Cinetoplastídeos/química , RNA Guia de Cinetoplastídeos/genética , Homologia de Sequência de Aminoácidos , Proteínas Virais/química , Proteínas Virais/genética
4.
Int J Mol Sci ; 19(3)2018 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-29495556

RESUMO

The new type of core oligosaccharide in Proteus penneri 40A and 41 lipopolysaccharides has been investigated by ¹H and 13C NMR spectroscopy, electrospray ionization mass spectrometry and chemical methods. Core oligosaccharides of both strains were chosen for structural analysis based on the reactivity of LPSs with serum against P. penneri 40A core oligosaccharide-diphtheria toxoid conjugate. Structural analyses revealed that P. penneri 40A and 41 LPSs possess an identical core oligosaccharide.


Assuntos
Antígenos de Bactérias/química , Lipopolissacarídeos/química , Oligossacarídeos/química , Proteus penneri/química , Antígenos de Bactérias/imunologia , Soros Imunes/imunologia , Lipopolissacarídeos/imunologia , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Oligossacarídeos/imunologia , Proteus penneri/imunologia , Espectrometria de Massas por Ionização por Electrospray , Relação Estrutura-Atividade
5.
Med Microbiol Immunol ; 205(6): 615-624, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27469376

RESUMO

The frequency of P. penneri isolation from hospital patients, mostly from urine and wounds, keeps on growing, and numerous isolates are multi-drug resistant. P. penneri rods produce lipopolysaccharide (LPS), which may lead to the septic shock. Until now, O-specific polysaccharide has been the best structurally and serologically characterized region of P. penneri LPS. It is worth having an insight into the serological specificity of both poly- and oligosaccharide parts of P. penneri LPS. The P. penneri core region is less structurally diverse than OPS, but still, among other enterobacterial LPS core regions, it is characterized by structural variability. In the present study, the serological reactivity of 25 P. penneri LPS core regions was analyzed by ELISA, passive immunohemolysis and Western blot technique using five polyclonal P. penneri antisera after or without their adsorption with the respective LPSs. The results allowed the assignment of the tested strains to five new core serotypes, which together with published serological studies led to the creation of the first serotyping scheme based on LPS core reactivities of 35 P. penneri and three P. mirabilis strains. Together with the O types scheme, it will facilitate assigning Proteus LPSs of clinical isolates into appropriate O and R serotypes.


Assuntos
Lipopolissacarídeos/imunologia , Proteus penneri/classificação , Proteus penneri/imunologia , Sorogrupo , Animais , Epitopos/imunologia , Soros Imunes , Lipopolissacarídeos/química , Proteus penneri/patogenicidade , Coelhos , Sorotipagem/métodos , Fatores de Virulência
6.
Carbohydr Res ; 407: 131-6, 2015 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-25771295

RESUMO

Proteus penneri is an opportunistic pathogen, which may cause severe diseases, most frequently urinary tract infections in immunocompromised patients. P. penneri Br 114 exhibiting a good swarming growth ability as an S-form strain was isolated from a wound of a patient in Lódz, Poland. Serological studies using ELISA and Western blotting and chemical analyses along with (1)H and (13)C NMR spectroscopy showed that the O-antigen (O-polysaccharide) of this strain is unique among the known Proteus serotypes O1-O79. It possesses a linear pentasaccharide repeating unit containing a partially O-acetylated amide of D-glucuronic acid (GlcA) with L-serine having the following structure: [structure: see text]. These data are a basis for creating a new Proteus serogroup, O80, so far represented by the single Br 114 isolate. The O80 is the 21st O-serogroup containing P. penneri strains and the fourth serogroup based on Proteus spp. clinical isolates from Lódz, Poland.


Assuntos
Antígenos O/química , Infecções por Proteus/microbiologia , Proteus penneri/classificação , Proteus penneri/isolamento & purificação , Sequência de Carboidratos , Humanos , Espectroscopia de Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Antígenos O/metabolismo , Polônia , Proteus penneri/imunologia , Sorotipagem
7.
Indian J Pathol Microbiol ; 57(3): 489-91, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25118755

RESUMO

Indole negative Proteus species are invariably incorrectly identified as Proteus mirabilis, often missing out isolates of Proteus penneri. We report a case of extended spectrum beta lactamase producing and multidrug-resistant P. penneri isolated from pus from pressure sore of a patient of road traffic accident. Correct and rapid isolation and identification of such resistant pathogen are important as they are significant nosocomial threat.


Assuntos
Farmacorresistência Bacteriana Múltipla , Infecções por Proteus/diagnóstico , Proteus penneri/enzimologia , Proteus penneri/isolamento & purificação , Infecção dos Ferimentos/diagnóstico , beta-Lactamases/metabolismo , Acidentes de Trânsito , Adulto , Técnicas Bacteriológicas , Erros de Diagnóstico , Humanos , Masculino , Infecções por Proteus/microbiologia , Infecção dos Ferimentos/microbiologia , Ferimentos e Lesões/complicações
8.
Acta Biochim Pol ; 61(1): 129-32, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24644555

RESUMO

Most Proteus lipopolysaccharides (LPSs) contain uronic acids or their amides with different amino acids, which together with other negatively charged components account for the acidic character of such LPS molecules. Previous studies have shown the significance of an amide of galacturonic acid with lysine [D-GalA(L-Lys)] for serological specificity of O-antigens from few P. mirabilis strains. In this work, the immunodominant role of GalALys was indicated for the P. penneri 42 LPS core region. The studies also showed the serological identity of core oligosaccharides from P. penneri 42 (O71), P. mirabilis 51/57 (O28) and R14/S1959 strains.


Assuntos
Ácidos Hexurônicos/administração & dosagem , Lipopolissacarídeos/administração & dosagem , Antígenos O/imunologia , Amidas , Ácidos Hexurônicos/química , Epitopos Imunodominantes/administração & dosagem , Lipopolissacarídeos/química , Lipopolissacarídeos/imunologia , Lisina/administração & dosagem , Lisina/química , Lisina/imunologia , Antígenos O/química , Proteus penneri/imunologia
9.
Antonie Van Leeuwenhoek ; 105(2): 423-30, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24271474

RESUMO

Bacteriosis has become a major economic problem in the farming of the Pacific white shrimp Penaeus vannamei. However, no definitive data are available about Proteus penneri infection in cultured P. vannamei and its control. In this study, a virulent strain NC was isolated from diseased P. vannamei suffering from red body disease and identified as a P. penneri isolate through phylogenetic analysis and ATB 32GN system. A phylogenetic constructed tree using the neighbour-joining method identified the NC isolate as a P. penneri strain. In addition, Bdellovibrio bacteriovorus conferred significant protection against P. penneri: it exhibited significant bacteriolytic effects on the pathogenic P. penneri, had a wide prey range towards Proteus pathogens, and displayed a good protective efficacy on experimental P. penneri infection in P. vannamei. To the best of our knowledge, this is the first report of farmed P. vannamei infected with P. penneri and its control with B. bacteriovorus.


Assuntos
Antibiose , Bdellovibrio/fisiologia , Penaeidae/microbiologia , Proteus penneri/isolamento & purificação , Proteus penneri/fisiologia , Animais , Técnicas de Tipagem Bacteriana , Bacteriólise , Bdellovibrio/crescimento & desenvolvimento , Análise por Conglomerados , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Dados de Sequência Molecular , Controle Biológico de Vetores/métodos , Filogenia , Proteus penneri/classificação , Proteus penneri/crescimento & desenvolvimento , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
10.
Pol J Microbiol ; 62(2): 211-6, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24053026

RESUMO

Our Department of General Microbiology created a wide collection of P. penneri isolates and classified most of them into 19 different O-serogroups. This work describes the classification of 12 remaining P. penneri strains. The lipopolysaccharides extracted from P. penneri strains were tested in an enzyme-linked immunosorbent assay (ELISA) with selected O-antisera against Proteus sp. strains. Homologous and cross-reacting systems were checked in: passive immunohemolysis (PIH), inhibition of ELISA and PIH and Western blot procedure. These studies led to the qualification of tested P. penneri strains to five Proteus sp. O-serogroups, thus completing the serological classification of the whole collection.


Assuntos
Proteus penneri/classificação , Ensaio de Imunoadsorção Enzimática , Humanos , Lipopolissacarídeos/classificação , Lipopolissacarídeos/metabolismo , Sorotipagem
11.
Adv Clin Exp Med ; 22(2): 165-75, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23709372

RESUMO

BACKGROUND: Proteus sp. strains isolated from patients with urinary tract infection (UTI) are often insensitive to the bactericidal action of normal human serum (NHS) which poses a clinical problem. The swarming phenomenon is an especially important factor in cases of UTIs gained through the ascending route. Both these virulence factors are connected with the cell surface components of bacteria, including lipopolysaccharide (LPS). OBJECTIVES: The resistance of Proteus bacilli to the bactericidal activity of NHS and the swarming phenomenon were investigated as well as the possible relationships between these virulence factors and the chemical structure of LPS. MATERIAL AND METHODS: The research was carried out on P. penneri and P. vulgaris species. Two preparations of sera were tested with respect to the bactericidal action of NHS. The ability of bacteria to swarm was checked on broth agar plates. The length of the O-specific part of LPS was estimated after poliacrylamide gel electrophoresis (PAGE) and staining with silver nitrate. RESULTS: Among the 62 tested Proteus strains, over 62% of Proteus vulgaris and 50% of Proteus penneri strains were sensitive to the bactericidal action of NHS. However, the number of resistant strains grew dramatically when serum with blocked complement activation via the alternative pathway was used. From 102 of the Proteus sp. Strains, only few were unable to swarm over the solid surface of the media. The remaining showed diverse ability to translocate. CONCLUSIONS: There was no definite correlation between the chemical structure of the O-specific chains of lipopolysaccharides and sensitivity or resistance of the Proteus sp. strains to NHS. Also, no significant relationships were found between the length or the chemical structure of the O-specific chains of the bacterial LPSs and the swarming phenomenon.


Assuntos
Atividade Bactericida do Sangue/fisiologia , Infecções por Proteus/microbiologia , Proteus penneri/crescimento & desenvolvimento , Proteus vulgaris/crescimento & desenvolvimento , Teste Bactericida do Soro/métodos , Infecções Urinárias/microbiologia , Humanos , Lipopolissacarídeos/metabolismo , Locomoção , Proteus penneri/patogenicidade , Proteus vulgaris/patogenicidade , Fatores de Virulência/metabolismo
12.
Indian J Med Res ; 135: 341-5, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22561620

RESUMO

BACKGROUND & OBJECTIVES: Indole negative Proteus species are invariably incorrectly identified as P. mirabilis, missing isolates of Proteus penneri. P. penneri is an invasive pathogen capable of causing major infectious diseases still seldom reported in individual cases. We report here the isolation, differentiation, characterization and typing of P. penneri from patients with different clinical infections. METHODS: Urine, pus and body fluids collected from patients in intensive care units, wards and out patients departments of a tertiary health care institute from north India were cultured. A total of 61 indole negative Proteus isolates were subjected to extended biochemical tests to differentiate and identify P. penneri from P. mirabilis including failure to produce ornithine decarboxylase (by 0% strains of P. penneri and 100% strains of P. mirabilis) besides P. penneri being uniformly salicin negative, non-utilizer of citrate but ferments sucrose and maltose. Antibiograms and Dienes phenomenon were performed to characterize and type P. penneri isolates besides screening for ß-lactamase production. RESULTS: Eight isolates of P. penneri were identified; four from urine, three from abdominal drain-fluid and one from diabetic foot ulcer. P. penneri was isolated as the sole pathogen in all patients having underlying disease; post-operatively. Swarming was not seen in the first strain on primary isolation and was poor in strain-4. All eight isolates were biochemically homologous but multi-drug resistant (MDR) with resistance to 6-8 drugs (up to 12). ß-lactamase production was seen in three of five isolates while Dienes phenomenon found four distinct types and discriminated strains differing in resistance even with a single drug. INTERPRETATION & CONCLUSIONS: A few additional biochemical tests identified P. penneri isolates; it infected patients with underlying disease and strains were MDR and heterogenous.


Assuntos
Proteus penneri/classificação , Proteus penneri/isolamento & purificação , Adolescente , Adulto , Idoso , Pré-Escolar , Resistência a Múltiplos Medicamentos , Feminino , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Infecções por Proteus/microbiologia , Infecções por Proteus/urina , Proteus penneri/efeitos dos fármacos , beta-Lactamases/metabolismo
13.
J Pediatr Surg ; 47(4): 808-11, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22498402

RESUMO

Fournier's gangrene is a rare urologic emergency in childhood that requires prompt diagnosis to deliver definitive and supportive care. Host susceptibility risk factors differ between adult and pediatric age groups with affected children usually otherwise systemically healthy. We present a case of Fournier's gangrene in a 2-year-old, from a genitourinary source of sepsis secondary to previously unreported genitourinary anatomical anomalies of congenital buried penis and hypospadias. Illustrative applied anatomy identifies the pathogenesis of this case, aiding recognition and understanding of this rapidly progressive and destructive pathology.


Assuntos
Gangrena de Fournier/diagnóstico , Hipospadia/complicações , Pênis/anormalidades , Pré-Escolar , Gangrena de Fournier/etiologia , Humanos , Masculino , Infecções por Proteus/diagnóstico , Infecções por Proteus/etiologia , Proteus penneri/isolamento & purificação
14.
Acta Biochim Pol ; 57(4): 529-32, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21060898

RESUMO

To extend the knowledge on the fragments of Proteus penneri lipopolysaccharide core regions, which determine the cross-reactions with specific antibodies, serological studies were performed by use of P. penneri 7 core-specific antiserum and Proteus sp. lipopolysaccharides. Different reactivity of the tested antiserum with three groups of antigens suggested differences in their core regions' epitope specificity. Comparing the results of the serological investigations with the previously determined structures of the core regions of the tested P. penneri lipopolysaccharides allowed distinguishing two potential tri- and tetrasaccharide epitopes and a third fragment which could not be determined precisely.


Assuntos
Epitopos , Lipopolissacarídeos/química , Lipopolissacarídeos/classificação , Proteus penneri/metabolismo , Western Blotting , Sequência de Carboidratos , Epitopos/química , Dados de Sequência Molecular
15.
Arch Immunol Ther Exp (Warsz) ; 56(2): 135-40, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18373243

RESUMO

INTRODUCTION: Proteus penneri lipopolysaccharide (LPS) core regions are characterized by a greater structural variability than that observed in other Enterobacteriaceae. This fact and the small amount of published data concerning the serological activity of this part of P. penneri LPS prompted an examination of which fragment might determine cross-reactions with antibodies. To date, such epitopes have been found in the LPS core regions of P. mirabilis and P. vulgaris strains. MATERIALS AND METHODS: Proteus sp. LPSs were tested with unabsorbed rabbit antisera by enzyme-linked immunosorbent assay (ELISA), sodium dodecyl sulfate polyacrylamide gel electrophoresis and Western blot, and once again by ELISA or passive immunohemolysis after the absorption of these antisera with selected LPSs. RESULTS: The serological studies of P. penneri 8 LPS demonstrated antibodies in the tested antisera recognizing a common epitope located in the core regions of six of the LPSs, i.e. P. penneri 8, 34, 133, 7, 14, and 15. Additionally, another type of antibody directed against some fragment of P. penneri 13 and the core regions of other LPSs investigated was observed in one antiserum. CONCLUSIONS: A distal, trisaccharide fragment of the P. penneri 8 LPS core region is suggested to determine the cross-reactions of the tested antisera with the six P. penneri LPSs.


Assuntos
Anticorpos Antibacterianos/imunologia , Epitopos , Lipopolissacarídeos/imunologia , Proteus penneri/imunologia , Animais , Western Blotting , Reações Cruzadas , Ensaio de Imunoadsorção Enzimática , Coelhos
16.
Arch Immunol Ther Exp (Warsz) ; 55(3): 187-91, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17557147

RESUMO

INTRODUCTION: Proteus rods are currently subdivided into five named species, i.e. Proteus mirabilis, P. vulgaris, P. penneri, P. hauseri, and P. myxofaciens, and three unnamed Proteus genomospecies 4 to 6. Based on the serospecificity of the lipopolysaccharide (LPS; O-antigen), strains of P. mirabilis and P. vulgaris were divided into 49 O-serogroups and 11 additional O-serogroups were proposed later. About 15 further O-serogroups have been proposed for the third medically important species, P. penneri. Here the serological classification of P. vulgaris strain TG 251, which does not belong to these serogroups, is reported. Serological investigations also allowed characterization of the epitope specificity of its LPS. MATERIALS AND METHODS: Purified LPSs from five Proteus strains were used as antigens in enzyme immunosorbent assay (EIA), SDS/PAGE, and Western blot and alkali-treated LPSs in the passive immunohemolysis (PIH) test, inhibition of PIH and EIA, and absorption of the rabbit polyclonal O-antisera with the respective LPS. RESULTS: The serological studies of P. vulgaris TG 251 LPS indicated the identity of its O-polysaccharide with that of P. penneri O65. The antibody specificities of P. vulgaris TG 251 and P. penneri O65 O-antisera, were described. CONCLUSIONS: P. vulgaris TG 251 was classified to the Proteus O65 serogroup. Two disaccharide-associated epitopes present in P. vulgaris TG 251 and P. penneri O65 LPSs are suggested to be responsible for cross-reactions with three heterologous Proteus strains.


Assuntos
Lipopolissacarídeos/imunologia , Antígenos O/imunologia , Proteus vulgaris/classificação , Proteus vulgaris/imunologia , Sorotipagem , Animais , Antígenos de Bactérias , Reações Cruzadas , Epitopos/química , Epitopos/imunologia , Lipopolissacarídeos/química , Lipopolissacarídeos/isolamento & purificação , Antígenos O/química , Proteus penneri/classificação , Proteus penneri/imunologia , Proteus penneri/isolamento & purificação , Proteus vulgaris/isolamento & purificação
17.
Arch Immunol Ther Exp (Warsz) ; 55(5): 347-52, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18219766

RESUMO

INTRODUCTION: Lipopolysaccharide (endotoxin, LPS) is an important potential virulence factor of Proteus rods. The serological specificity of the bacteria is defined by the structure of the O-polysaccharide chain (O-antigen) of the LPS. Until now, 76 O-serogroups have been differentiated among Proteus strains. MATERIALS AND METHODS: LPSs were isolated from Proteus mirabilis TG 83, TG 319, and CCUG 10700 (OA) strains by phenol/water extraction. Antisera were raised by immunization of rabbits with heat-killed bacteria. Serological investigations were performed using enzyme immunosorbent assay, passive immunohemolysis, inhibition of both assays, absorption of antisera, and Western blot. RESULTS: The cross-reactive epitope shared by these strains and P. penner O72a,O72b is located on the O-polysaccharide and is most likely associated with an alpha-D-Glcp-(1-->6)-beta-D-GalpNAc disaccharide fragment. The serological data indicated the occurrence of two core types in the LPSs studied, one characteristic for P. mirabilis TG 319 and CCUG 10700 (OA) and the other for P. mirabilis TG 83 and O57. CONCLUSIONS: The serological and structural data showed that P. mirabilis TG 83, TG 319, CCUG 10700 (OA), and O57 have the same O-antigen structure and could be qualified to the Proteus O57 serogroup.


Assuntos
Antígenos O/química , Antígenos O/imunologia , Proteus mirabilis/química , Proteus mirabilis/imunologia , Animais , Proteus mirabilis/classificação , Proteus penneri/química , Proteus penneri/imunologia , Coelhos , Testes Sorológicos
18.
Enferm Infecc Microbiol Clin ; 24 Suppl 1: 8-13, 2006 Oct.
Artigo em Espanhol | MEDLINE | ID: mdl-17125662

RESUMO

Proteus penneri, formerly P. vulgaris biogroup 1, was recognized as a new species in 1982. This species is associated with clinical processes similar to those involving P. mirabilis and P. vulgaris and expresses similar pathogenic determinants. In clinical samples, P. penneri is mainly isolated from urine (50%), wound and soft tissue exudates (25%), and blood cultures (15%), mostly of nosocomial origin. Although P. penneri is easy to identify, it can be misidentified as P. vulgaris by automatic systems that do not include the indol test result in the identification process. This species has a characteristic susceptibility profile, essentially due to the production of the chromosomal inducible beta-lactamase HugA, which presents a high homology (86%) with CumA from P. vulgaris. HugA is inhibited by clavulanic acid and determines resistance to aminopenicillins and first- and second-generation cephalosporins, including cefuroxime, but does not affect cephamycins or carbapenems, and is inhibited by clavulanic acid. HugA is derepressed due to mutational processes in gene regulators, affecting the activity of cefotaxime and, to a much lesser extent, that of ceftazidime and aztreonam. This phenotype resembles the production of an extended spectrum beta-lactamase. Like other Proteus species, P. penneri is resistant to tetracyclines and should be considered resistant to nitrofurantoin.


Assuntos
Infecções por Proteus , Proteus penneri , Resistência Microbiana a Medicamentos , Humanos , Infecções por Proteus/epidemiologia , Proteus penneri/efeitos dos fármacos , Proteus penneri/patogenicidade
19.
Enferm. infecc. microbiol. clín. (Ed. impr.) ; 24(supl.1): 8-13, oct. 2006. graf, tab
Artigo em Espanhol | IBECS | ID: ibc-174765

RESUMO

Proteus penneri, anteriormente denominado Proteus vulgaris biogrupo 1, fue reconocido como especie nueva en 1982. Se asocia a procesos similares a los que producen Proteus mirabilis y Proteus vulgaris y comparte con ellos factores de patogenicidad. En muestras clínicas, se aísla esencialmente de orina (50%), exudados de piel y tejidos blandos (25%) y hemocultivos (15%), sobre todo en infección nosocomial. Su identificación no es problemática, aunque puede confundirse con P. vulgaris en los sistemas automáticos que no utilicen la prueba de indol en los procesos de identificación. Tiene un perfil de resistencia particular debido a la producción de la β-lactamasa cromosómica inducible HugA, con una elevada homología (86%) con CumA de P. vulgaris. HugA determina resistencia a aminopenicilinas y cefalosporinas de primera y segunda generación, incluyendo la cefuroxima, pero no afecta a las cefamicinas ni los carbapénemes, y se inhibe por el ácido clavulánico. La síntesis de HugA se desreprime debido a mutaciones en los genes reguladores, con lo que se afectan la actividad de la cefotaxima y, en mucha menor medida, la de la ceftazidima y el aztreonam. Este fenotipo puede confundirse con la producción de una β-lactamasa de espectro extendido. Al igual que otros Proteus penneri, es resistente a las tetraciclinas y debe considerarse resistente a la nitrofurantoína


Proteus penneri, formerly P. vulgaris biogroup 1, was recognized as a new species in 1982. This species is associated with clinical processes similar to those involving P. mirabilis and P. vulgaris and expresses similar pathogenic determinants. In clinical samples, P. penneri is mainly isolated from urine (50%), wound and soft tissue exudates (25%), and blood cultures (15%), mostly of nosocomial origin. Although P. penneri is easy to identify, it can be misidentified as P. vulgaris by automatic systems that do not include the indol test result in the identification process. This species has a characteristic susceptibility profile, essentially due to the production of the chromosomal inducible β-lactamase HugA, which presents a high homology (86%) with CumA from P. vulgaris. HugA is inhibited by clavulanic acid and determines resistance to aminopenicillins and first- and second-generation cephalosporins, including cefuroxime, but does not affect cephamycins or carbapenems, and is inhibited by clavulanic acid. HugA is derepressed due to mutational processes in gene regulators, affecting the activity of cefotaxime and, to a much lesser extent, that of ceftazidime and aztreonam. This phenotype resembles the production of an extended spectrum β-lactamase. Like other Proteusspecies, P. penneri is resistant to tetracyclines and should be considered resistant to nitrofurantoin


Assuntos
Humanos , Resistência Microbiana a Medicamentos , Infecções por Proteus/epidemiologia , Proteus penneri , Proteus penneri/patogenicidade
20.
Enferm Infecc Microbiol Clin ; 23(3): 122-6, 2005 Mar.
Artigo em Espanhol | MEDLINE | ID: mdl-15757582

RESUMO

INTRODUCTION: The aim of this study was to evaluate betalactam resistance within the genus Proteus and characterize the betalactamases responsible for this resistance. METHODS: We analyzed 99 strains (87, P. mirabilis; 10 P. vulgaris, and 2, P. penneri) isolated from patients at one University Hospital. Antibiotic susceptibility tests were performed according to NCCLS recommendations. Presence of extended spectrum betalactamases (ESBL) was inferred by both double disk diffusion tests and minimum inhibitory concentration (MIC) of third and fourth generation cephalosporins alone and in the presence of clavulanic acid. Isoelectric points (pI) of the enzymes were estimated by isoelectrofocusing and the presence of the encoding genes was confirmed by polymerase chain reaction (PCR). RESULTS: A broad spectrum betalactamase could be detected in those isolates (28%) resistant to penicillin and first generation cephalosporins while CTX-M-2 enzyme could be detected in P. mirabilis isolates resistant to third and fourth generation cephalosporins (18%). One of the P. vulgaris displayed reduced susceptibility to cefotaxime due to an enzyme of pI 7.4, while resistance to cefotaxime in one P. penneri was related to an enzyme of pI 6.8. Both enzymes were active on cefotaxime (1,000 mg/l) in the iodometric assay. CONCLUSION: The broad extended spectrum betalactamase within genus Proteus was TEM-1, while CTX-M-2 was the ESBL responsible for the third and fourth generation cephalosporins in P. mirabilis. In P. vulgaris and P. penneri this resistance was associated with the hyperproduction of the chromosomal encoded betalactamase.


Assuntos
Proteínas de Bactérias/genética , Cefalosporinas/farmacologia , Proteus/efeitos dos fármacos , Resistência beta-Lactâmica , beta-Lactamases/genética , Argentina/epidemiologia , Proteínas de Bactérias/isolamento & purificação , Proteínas de Bactérias/metabolismo , Cefotaxima/metabolismo , Cefotaxima/farmacologia , Cefalosporinas/classificação , Cefalosporinas/metabolismo , Cromossomos Bacterianos/genética , Genes Bacterianos , Genótipo , Humanos , Ponto Isoelétrico , Testes de Sensibilidade Microbiana , Fenótipo , Proteus/enzimologia , Proteus/genética , Infecções por Proteus/epidemiologia , Infecções por Proteus/microbiologia , Proteus mirabilis/efeitos dos fármacos , Proteus mirabilis/enzimologia , Proteus mirabilis/genética , Proteus penneri/efeitos dos fármacos , Proteus penneri/enzimologia , Proteus penneri/genética , Proteus vulgaris/efeitos dos fármacos , Proteus vulgaris/enzimologia , Proteus vulgaris/genética , Especificidade da Espécie , Resistência beta-Lactâmica/genética , beta-Lactamases/isolamento & purificação , beta-Lactamases/metabolismo
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