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1.
Org Lett ; 25(23): 4400-4405, 2023 06 16.
Article in English | MEDLINE | ID: mdl-37284758

ABSTRACT

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.


Subject(s)
Proteus penneri , Proteus vulgaris , Carbohydrate Sequence , O Antigens , Disaccharides
2.
Int J Biol Macromol ; 163: 1168-1174, 2020 Nov 15.
Article in English | MEDLINE | ID: mdl-32652158

ABSTRACT

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.


Subject(s)
O Antigens/chemistry , Polysaccharides, Bacterial/chemistry , Proteus penneri/chemistry , Proteus penneri/classification , Serogroup , Enzyme-Linked Immunosorbent Assay , Humans , Mass Spectrometry , Molecular Structure , Nuclear Magnetic Resonance, Biomolecular , O Antigens/immunology , Phosphorylation , Proteus penneri/immunology
3.
Nat Commun ; 11(1): 2730, 2020 06 01.
Article in English | MEDLINE | ID: mdl-32483187

ABSTRACT

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.


Subject(s)
Bacteria/metabolism , Bacteriophages/metabolism , CRISPR-Cas Systems , DNA/metabolism , RNA, Guide, Kinetoplastida/metabolism , Viral Proteins/metabolism , Amino Acid Sequence , Bacteria/genetics , Bacteria/virology , Bacterial Proteins/chemistry , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Bacteriophages/genetics , Cryoelectron Microscopy , DNA/chemistry , DNA/genetics , Models, Molecular , Multiprotein Complexes/chemistry , Multiprotein Complexes/metabolism , Multiprotein Complexes/ultrastructure , Nucleic Acid Conformation , Protein Binding , Protein Conformation , Proteus penneri/genetics , Proteus penneri/metabolism , Proteus penneri/virology , RNA, Guide, Kinetoplastida/chemistry , RNA, Guide, Kinetoplastida/genetics , Sequence Homology, Amino Acid , Viral Proteins/chemistry , Viral Proteins/genetics
4.
Int J Mol Sci ; 19(3)2018 Feb 28.
Article in English | MEDLINE | ID: mdl-29495556

ABSTRACT

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.


Subject(s)
Antigens, Bacterial/chemistry , Lipopolysaccharides/chemistry , Oligosaccharides/chemistry , Proteus penneri/chemistry , Antigens, Bacterial/immunology , Immune Sera/immunology , Lipopolysaccharides/immunology , Magnetic Resonance Spectroscopy , Molecular Structure , Oligosaccharides/immunology , Proteus penneri/immunology , Spectrometry, Mass, Electrospray Ionization , Structure-Activity Relationship
5.
Med Microbiol Immunol ; 205(6): 615-624, 2016 Dec.
Article in English | MEDLINE | ID: mdl-27469376

ABSTRACT

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.


Subject(s)
Lipopolysaccharides/immunology , Proteus penneri/classification , Proteus penneri/immunology , Serogroup , Animals , Epitopes/immunology , Immune Sera , Lipopolysaccharides/chemistry , Proteus penneri/pathogenicity , Rabbits , Serotyping/methods , Virulence Factors
6.
Carbohydr Res ; 407: 131-6, 2015 Apr 30.
Article in English | MEDLINE | ID: mdl-25771295

ABSTRACT

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.


Subject(s)
O Antigens/chemistry , Proteus Infections/microbiology , Proteus penneri/classification , Proteus penneri/isolation & purification , Carbohydrate Sequence , Humans , Magnetic Resonance Spectroscopy/methods , Male , Middle Aged , O Antigens/metabolism , Poland , Proteus penneri/immunology , Serotyping
7.
Indian J Pathol Microbiol ; 57(3): 489-91, 2014.
Article in English | MEDLINE | ID: mdl-25118755

ABSTRACT

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.


Subject(s)
Drug Resistance, Multiple, Bacterial , Proteus Infections/diagnosis , Proteus penneri/enzymology , Proteus penneri/isolation & purification , Wound Infection/diagnosis , beta-Lactamases/metabolism , Accidents, Traffic , Adult , Bacteriological Techniques , Diagnostic Errors , Humans , Male , Proteus Infections/microbiology , Wound Infection/microbiology , Wounds and Injuries/complications
8.
Acta Biochim Pol ; 61(1): 129-32, 2014.
Article in English | MEDLINE | ID: mdl-24644555

ABSTRACT

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.


Subject(s)
Hexuronic Acids/administration & dosage , Lipopolysaccharides/administration & dosage , O Antigens/immunology , Amides , Hexuronic Acids/chemistry , Immunodominant Epitopes/administration & dosage , Lipopolysaccharides/chemistry , Lipopolysaccharides/immunology , Lysine/administration & dosage , Lysine/chemistry , Lysine/immunology , O Antigens/chemistry , Proteus penneri/immunology
9.
Antonie Van Leeuwenhoek ; 105(2): 423-30, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24271474

ABSTRACT

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.


Subject(s)
Antibiosis , Bdellovibrio/physiology , Penaeidae/microbiology , Proteus penneri/isolation & purification , Proteus penneri/physiology , Animals , Bacterial Typing Techniques , Bacteriolysis , Bdellovibrio/growth & development , Cluster Analysis , DNA, Bacterial/chemistry , DNA, Bacterial/genetics , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , Molecular Sequence Data , Pest Control, Biological/methods , Phylogeny , Proteus penneri/classification , Proteus penneri/growth & development , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNA
10.
Pol J Microbiol ; 62(2): 211-6, 2013.
Article in English | MEDLINE | ID: mdl-24053026

ABSTRACT

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.


Subject(s)
Proteus penneri/classification , Enzyme-Linked Immunosorbent Assay , Humans , Lipopolysaccharides/classification , Lipopolysaccharides/metabolism , Serotyping
11.
Adv Clin Exp Med ; 22(2): 165-75, 2013.
Article in English | MEDLINE | ID: mdl-23709372

ABSTRACT

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.


Subject(s)
Blood Bactericidal Activity/physiology , Proteus Infections/microbiology , Proteus penneri/growth & development , Proteus vulgaris/growth & development , Serum Bactericidal Test/methods , Urinary Tract Infections/microbiology , Humans , Lipopolysaccharides/metabolism , Locomotion , Proteus penneri/pathogenicity , Proteus vulgaris/pathogenicity , Virulence Factors/metabolism
12.
Indian J Med Res ; 135: 341-5, 2012 Mar.
Article in English | MEDLINE | ID: mdl-22561620

ABSTRACT

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.


Subject(s)
Proteus penneri/classification , Proteus penneri/isolation & purification , Adolescent , Adult , Aged , Child, Preschool , Drug Resistance, Multiple , Female , Humans , Male , Microbial Sensitivity Tests , Middle Aged , Proteus Infections/microbiology , Proteus Infections/urine , Proteus penneri/drug effects , beta-Lactamases/metabolism
13.
J Pediatr Surg ; 47(4): 808-11, 2012 Apr.
Article in English | MEDLINE | ID: mdl-22498402

ABSTRACT

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.


Subject(s)
Fournier Gangrene/diagnosis , Hypospadias/complications , Penis/abnormalities , Child, Preschool , Fournier Gangrene/etiology , Humans , Male , Proteus Infections/diagnosis , Proteus Infections/etiology , Proteus penneri/isolation & purification
14.
Acta Biochim Pol ; 57(4): 529-32, 2010.
Article in English | MEDLINE | ID: mdl-21060898

ABSTRACT

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.


Subject(s)
Epitopes , Lipopolysaccharides/chemistry , Lipopolysaccharides/classification , Proteus penneri/metabolism , Blotting, Western , Carbohydrate Sequence , Epitopes/chemistry , Molecular Sequence Data
15.
Arch Immunol Ther Exp (Warsz) ; 56(2): 135-40, 2008.
Article in English | MEDLINE | ID: mdl-18373243

ABSTRACT

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.


Subject(s)
Antibodies, Bacterial/immunology , Epitopes , Lipopolysaccharides/immunology , Proteus penneri/immunology , Animals , Blotting, Western , Cross Reactions , Enzyme-Linked Immunosorbent Assay , Rabbits
16.
Arch Immunol Ther Exp (Warsz) ; 55(3): 187-91, 2007.
Article in English | MEDLINE | ID: mdl-17557147

ABSTRACT

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.


Subject(s)
Lipopolysaccharides/immunology , O Antigens/immunology , Proteus vulgaris/classification , Proteus vulgaris/immunology , Serotyping , Animals , Antigens, Bacterial , Cross Reactions , Epitopes/chemistry , Epitopes/immunology , Lipopolysaccharides/chemistry , Lipopolysaccharides/isolation & purification , O Antigens/chemistry , Proteus penneri/classification , Proteus penneri/immunology , Proteus penneri/isolation & purification , Proteus vulgaris/isolation & purification
17.
Arch Immunol Ther Exp (Warsz) ; 55(5): 347-52, 2007.
Article in English | MEDLINE | ID: mdl-18219766

ABSTRACT

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.


Subject(s)
O Antigens/chemistry , O Antigens/immunology , Proteus mirabilis/chemistry , Proteus mirabilis/immunology , Animals , Proteus mirabilis/classification , Proteus penneri/chemistry , Proteus penneri/immunology , Rabbits , Serologic Tests
18.
Enferm Infecc Microbiol Clin ; 24 Suppl 1: 8-13, 2006 Oct.
Article in Spanish | MEDLINE | ID: mdl-17125662

ABSTRACT

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.


Subject(s)
Proteus Infections , Proteus penneri , Drug Resistance, Microbial , Humans , Proteus Infections/epidemiology , Proteus penneri/drug effects , Proteus penneri/pathogenicity
19.
Enferm. infecc. microbiol. clín. (Ed. impr.) ; 24(supl.1): 8-13, oct. 2006. graf, tab
Article in Spanish | IBECS | ID: ibc-174765

ABSTRACT

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


Subject(s)
Humans , Drug Resistance, Microbial , Proteus Infections/epidemiology , Proteus penneri , Proteus penneri/pathogenicity
20.
Enferm Infecc Microbiol Clin ; 23(3): 122-6, 2005 Mar.
Article in Spanish | MEDLINE | ID: mdl-15757582

ABSTRACT

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.


Subject(s)
Bacterial Proteins/genetics , Cephalosporins/pharmacology , Proteus/drug effects , beta-Lactam Resistance , beta-Lactamases/genetics , Argentina/epidemiology , Bacterial Proteins/isolation & purification , Bacterial Proteins/metabolism , Cefotaxime/metabolism , Cefotaxime/pharmacology , Cephalosporins/classification , Cephalosporins/metabolism , Chromosomes, Bacterial/genetics , Genes, Bacterial , Genotype , Humans , Isoelectric Point , Microbial Sensitivity Tests , Phenotype , Proteus/enzymology , Proteus/genetics , Proteus Infections/epidemiology , Proteus Infections/microbiology , Proteus mirabilis/drug effects , Proteus mirabilis/enzymology , Proteus mirabilis/genetics , Proteus penneri/drug effects , Proteus penneri/enzymology , Proteus penneri/genetics , Proteus vulgaris/drug effects , Proteus vulgaris/enzymology , Proteus vulgaris/genetics , Species Specificity , beta-Lactam Resistance/genetics , beta-Lactamases/isolation & purification , beta-Lactamases/metabolism
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