A method of isolation of the antiphage agent found in the preparations of bacterial DNA was developed. Chemical analysis of the preparations has shown that according to their qualitative and quantitative composition they are identical to the lipopolysaccharide of the bacterial membrane. On the basis of data on the antiphage activity of the D-LPS from E. coli B and E. coli K12 and on the basis of presumed analogy between the inactivation of the phage by the D-LPS preparations and the phage -- cell interaction it is believed that different parts of the LPS serve as receptors for the phages T7 and T4: O-specific polysaccharide for T4 and core LPS for T7. On the basis of data on the activity of D-LPS of two species of the genus Aerobacter against the phage T7 it is presumed that Aerobacer and Escherichia are related according to the structure of their core LPS.

• MeSH
• bakteriální polysacharidy analýza   farmakologie   MeSH
• DNA bakterií analýza   MeSH
• druhová specificita MeSH
• Enterobacter analýza   MeSH
• Enterobacteriaceae analýza   MeSH
• Escherichia coli analýza   MeSH
• kolifágy účinky léků   MeSH
• lipopolysacharidy analýza   farmakologie   MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• bakteriální polysacharidy MeSH
• DNA bakterií MeSH
• lipopolysacharidy MeSH

A method of isolation of the antiphage agent found in the preparations of bacterial DNA was developed. Chemical analysis of the preparations has shown that according to their qualitative and quantitative composition they are identical to the lipopolysaccharide of the bacterial membrane. On the basis of data on the antiphage activity of the D-LPS from E. coli B and E. coli K12 and on the basis of presumed analogy between the inactivation of the phage by the D-LPS preparations and the phage--cell interaction it is believed that different parts of the LPS serve as receptors for the phages T7 and T4: O-specific polysaccharide for T4 and core LPS for T7. On the basis of data on the activity of D-LPS of two species of the genus Aerobacter against the phage T7 it is presumed that Aerobacer and Escherichia are related according to the structure of their core LPS.

• MeSH
• antivirové látky analýza   izolace a purifikace   MeSH
• bakteriální polysacharidy analýza   izolace a purifikace   MeSH
• DNA bakterií * MeSH
• druhová specificita MeSH
• Enterobacter MeSH
• Escherichia coli * MeSH
• kolifágy * MeSH
• lipopolysacharidy analýza   izolace a purifikace   MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• antivirové látky MeSH
• bakteriální polysacharidy MeSH
• DNA bakterií * MeSH
• lipopolysacharidy MeSH

Many ecological experiments are based on the extraction and downstream analyses of microorganisms from different environmental samples. Due to its high throughput, cost-effectiveness and rapid performance, Matrix Assisted Laser Desorption/Ionization Mass Spectrometry with Time-of-Flight detector (MALDI-TOF MS), which has been proposed as a promising tool for bacterial identification and classification, could be advantageously used for dereplication of recurrent bacterial isolates. In this study, we compared whole-cell MALDI-TOF MS-based analyses of 49 bacterial cultures to two well-established bacterial identification and classification methods based on nearly complete 16S rRNA gene sequence analyses: a phylotype-based approach, using a closest type strain assignment, and a sequence similarity-based approach involving a 98.65% sequence similarity threshold, which has been found to best delineate bacterial species. Culture classification using reference-based MALDI-TOF MS was comparable to that yielded by phylotype assignment up to the genus level. At the species level, agreement between 16S rRNA gene analysis and MALDI-TOF MS was found to be limited, potentially indicating that spectral reference databases need to be improved. We also evaluated the mass spectral similarity technique for species-level delineation which can be used independently of reference databases. We established optimal mass spectral similarity thresholds which group MALDI-TOF mass spectra of common environmental isolates analogically to phylotype- and sequence similarity-based approaches. When using a mass spectrum similarity approach, we recommend a mass range of 4-10 kDa for analysis, which is populated with stable mass signals and contains the majority of phylotype-determining peaks. We show that a cosine similarity (CS) threshold of 0.79 differentiate mass spectra analogously to 98.65% species-level delineation sequence similarity threshold, with corresponding precision and recall values of 0.70 and 0.73, respectively. When matched to species-level phylotype assignment, an optimal CS threshold of 0.92 was calculated, with associated precision and recall values of 0.83 and 0.64, respectively. Overall, our research indicates that a similarity-based MALDI-TOF MS approach can be routinely used for efficient dereplication of isolates for downstream analyses, with minimal loss of unique organisms. In addition, MALDI-TOF MS analysis has further improvement potential unlike 16S rRNA gene analysis, whose methodological limits have reached a plateau.

• Klíčová slova
• 16S rRNA gene, MALDI BioTyper, MALDI-TOF mass spectrometry (MS), bacterial identification, bacterial isolation, dereplication of isolates, species delineation,
• Publikační typ
• časopisecké články MeSH

The authors present a brief account of the history of the genesis of a new genus of bacteria Mobiluncus. They describe their own experience with the cultivation and identification of this microorganism. From 300 specimens of vaginal smears it proved possible to cultivate Mobiluncus sp. in 15 instances whereby all positive cultivations correlated with the microscopic vaginal picture IIb. The majority of patients where Mobiluncus was proved by cultivation had clinical symptoms of the syndrome of bacterial vaginosis which suggests the participation of this organism in the aetiology of the disease.

• MeSH
• anaerobní bakterie * klasifikace   izolace a purifikace   MeSH
• lidé MeSH
• vagina mikrobiologie   MeSH
• vaginitida etiologie   mikrobiologie   MeSH
• Check Tag
• lidé MeSH
• ženské pohlaví MeSH
• Publikační typ
• anglický abstrakt MeSH
• časopisecké články MeSH

PURPOSE OF THE STUDY: Various techniques are used for detection of pathogens in musculoskeletal infection. These methods differ with respect to reliability and ease of handling. A prospective study was performed to evaluate the efficacy of three intraoperative techniques. MATERIAL AND METHODS: In 20 cases (18 patients) with clinically confirmed acute musculoskeletal infections, intraoperative collected swab samples, tissue samples and fluid samples injected into standard blood culture vials were used for microbiological diagnosis. Identification of bacteria, time necessary for detection and ease of handling during surgery was evaluated. RESULTS: In 19 cases bacterial growth was demonstrated using either intraoperative swabs or blood culture technique (95% sensitivity), whereas 18 tissue biopsies were positive (90% sensitivity. 27 bacterial species were isolated. In 18 instances for the swab technique, 14 instances for the tissue biopsy and 4 operations for the blood culture vials, ease of handling was rated as excellent. DISCUSSION: The study demonstrated differences between the three tested methods with respect to ease of handling. With respect to the number of detected organisms and time for their detection there are no significant differences. These last findings are in contrast to of the results of other authors. The reason for this could be that during operative dissection an accurate and specific collection of specimens from the acute deep infected soft tissues and bones independent from the type of surgical procedure is possible. Therefore, even with the swab method a high amount of microorganisms can be recovered. Especially for intraarticular infections, fluid samples injected into standard blood vials is a practical method for the surgeon. In acute musculoskeletal infections other than joint infections, there is less benefit for the blood culture vials. CONCLUSION: Intraoperative swab technique yields valid results comparable to other techniques and is an accurate technique for detection of pathogens from acute musculoskeletal infections. Key words: implant, infections, bacteriological techniques, comparative study.

• MeSH
• akutní nemoc MeSH
• Bacteria izolace a purifikace   MeSH
• bakteriální infekce mikrobiologie   chirurgie   MeSH
• bakteriologické techniky MeSH
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• muskuloskeletální nemoci mikrobiologie   chirurgie   MeSH
• senioři MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• srovnávací studie MeSH

The colorimetric DNA-DNA hybridization method for the identification of 18 strains of Aeromonas spp. isolated from human stools was used. Bacterial isolates were also examined by phenotypic characteristics. On the basis of biochemical tests 13 strains were included in phenogroup A. caviae and 5 strains in A. sobria. Identification to the species level was obtained by colorimetric hybridization method. DNA-DNA similarity values showed that isolates of A. caviae group belong to hybridization group (HG) 4 whereas isolates of A. sobria belong to HG 8/10. DNA relatedness results obtained by the colorimetric method showed good agreement with values detected by the spectrophotometric method. The background in the colorimetric method is lower than in the spectrophotometric one. Results of this study indicate the usefulness of the colorimetric DNA-DNA hybridization in microplates method for the identification of Aeromonas genomic species, isolated from human diarrheal stools.

• MeSH
• Aeromonas klasifikace   genetika   izolace a purifikace   MeSH
• difenylamin MeSH
• dítě MeSH
• DNA bakterií analýza   genetika   MeSH
• dospělí MeSH
• druhová specificita MeSH
• feces mikrobiologie   MeSH
• gramnegativní bakteriální infekce mikrobiologie   MeSH
• hybridizace nukleových kyselin metody   MeSH
• indikátory a reagencie MeSH
• kojenec MeSH
• kolorimetrie metody   MeSH
• lidé MeSH
• předškolní dítě MeSH
• průjem mikrobiologie   MeSH
• Check Tag
• dítě MeSH
• dospělí MeSH
• kojenec MeSH
• lidé MeSH
• předškolní dítě MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• srovnávací studie MeSH
• Názvy látek
• difenylamin MeSH
• DNA bakterií MeSH
• indikátory a reagencie MeSH

Bacterial diseases are common in ornamental fish, more frequently associated with ubiquitous bacteria from the aquarium environment. The disease can lead to fish mortality and cause high economic losses if not rapidly controlled. The aim of this study was to identify the main causative bacterial agents of infection in ornamental fish with different clinical signs. A total of 126 freshwater fish, from 12 families and 38 species, with clinical signs were collected in a wholesaler in São Paulo, SP, Brazil. Samples were taken from the eye, skin ulcers, kidneys, and gills, plated on MacConkey, CHROMagar Orientation, and blood agar and incubated under aerobic and anaerobic conditions. Bacterial identification was performed by MALDI-TOF mass spectrometry. From the 126 studied animals, 112 were positive for bacterial isolation. Among the positive animals, 32.1% presented infection caused by a single bacterial species, while in the remaining 67.9%, two to six different bacterial species were identified. A total of 259 bacterial strains were obtained and classified among 46 bacterial species. The species of higher frequency were Aeromonas veronii (26.3%), Aeromonas hydrophilla (16.2%), Shewanella putrefaciens (7.3%), Citrobacter freundii (8.1%), Vibrio albensis (5.8%), and Klebsiella pneumoniae (4.2%). MALDI-TOF MS showed to be a rapid method for diagnosis of bacterial disease outbreaks in ornamental fish establishments.

• Klíčová slova
• Animal health, Bacterial disease, Diagnosis in fish, Fish disease,
• MeSH
• Aeromonas * MeSH
• lidé MeSH
• nemoci ryb * MeSH
• ryby MeSH
• sladká voda MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Brazílie MeSH

Matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS) represents a simple reliable approach for rapid bacterial identification based on specific peptide/protein fingerprints. However, cell-wall characteristics of mycobacterial species, and their well known stability, complicate MALDI-TOF MS profiling analysis. In this study, we tested two recently published protocols for inactivation and disruption of mycobacteria, and we also examined the influence of different culture conditions (four culture media and five cultivation times) on mass spectral quality and the discriminatory power of the method. We found a significant influence of sample pretreatment method and culture medium on species identification and differentiation for a total of 10 strains belonging to Mycobacterium phlei and Mycobacterium smegmatis. Optimum culture conditions yielding the highest identification success rate against the BioTyper database (Bruker Daltonics) and permitting the possibility of automatic acquisition of mass spectra were found to be distinct for the two mycobacterial species examined. Similarly, individual changes in growth conditions had diverse effects on the two species. For these reasons, thorough control over cultivation conditions should always be employed to maximize the performance and discriminatory power of MALDI-TOF MS profiling, and cultivation conditions must be optimized separately for individual groups of mycobacterial species/strains.

• Klíčová slova
• MALDI-TOF MS, Mycobacterium phlei, Mycobacterium smegmatis, mycobacteria profiling, strain differentiation,
• MeSH
• kultivační média farmakologie   MeSH
• Mycobacterium účinky léků   MeSH
• spektrometrie hmotnostní - ionizace laserem za účasti matrice metody   MeSH
• techniky typizace bakterií MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• kultivační média MeSH

Molecular biological methods based on genus-specific PCR, species-specific PCR, and amplified ribosomal DNA restriction analysis (ARDRA) of two PCR amplicons (523 and 914bp) using six restriction enzymes were used to differentiate among species of Bifidobacterium. The techniques were established using DNA from 16 type and reference strains of bifidobacteria of 11 species. The discrimination power of 914bp amplicon digestion was higher than that of 523bp amplicon digestion. The 914bp amplicon digestion by six restrictases provided unique patterns for nine species; B. catenulatum and B. pseudocatenulatum were not differentiated yet. The NciI digestion of the 914bp PCR product enabled to discriminate between each of B. animalis, B. lactis, and B. gallicum. The reference strain B. adolescentis CCM 3761 was reclassified as a member of the B. catenulatum/B. pseudocatenulatum group. The above-mentioned methods were applied for the identification of seven strains of Bifidobacterium spp. collected in the Culture Collection of Dairy Microorganisms (CCDM). The strains collected in CCDM were differentiated to the species level. Six strains were identified as B. lactis, one strain as B. adolescentis.

• MeSH
• Bifidobacterium klasifikace   genetika   izolace a purifikace   MeSH
• DNA bakterií chemie   genetika   MeSH
• druhová specificita MeSH
• fylogeneze MeSH
• lidé MeSH
• mezerníky ribozomální DNA chemie   genetika   MeSH
• polymerázová řetězová reakce metody   MeSH
• polymorfismus délky restrikčních fragmentů * MeSH
• RNA ribozomální 16S chemie   genetika   MeSH
• RNA ribozomální 23S chemie   genetika   MeSH
• sekvence nukleotidů MeSH
• sekvenční seřazení MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• DNA bakterií MeSH
• mezerníky ribozomální DNA MeSH
• RNA ribozomální 16S MeSH
• RNA ribozomální 23S MeSH

A set of 204 taxonomically well-defined strains belonging to 17 Acinetobacter spp., including 11 recently described species (A. albensis, A. bohemicus, A. colistiniresistens, A. courvalinii. A. dispersus, A. gandensis, A. modestus, A. proteolyticus, A. seifertii, A. variabilis, and A. vivianii) and six species of the so-called haemolytic clade (A. beijerinckii, A. gyllenbergii, A. haemolyticus, A. junii, A. parvus, and A. venetianus), were subjected to MALDI-TOF mass spectrometric profiling. The identification outputs were evaluated using the current version (8.0.0.0) of the commercially available Bruker Daltonics, Biotyper database, which does not contain reference entries for six of the species tested. Up to 29% of the strains were falsely identified as different Acinetobacter spp. present in the Biotyper database, resulting mostly from the close phylogenetic relationship of species of the haemolytic clade. To obtain more reliable identification, extending the commercial database showed only partial improvement, while the use of an alternative MALDI matrix solution (strongly acidified ferulic acid) allowed correct identification of nearly all problematic strains.

• Klíčová slova
• Acinetobacter spp., Bacteria profiling, BioTyper, MALDI-TOF MS,
• MeSH
• Acinetobacter klasifikace   genetika   izolace a purifikace   MeSH
• bakteriální geny MeSH
• databáze genetické MeSH
• fylogeneze MeSH
• infekce bakteriemi rodu Acinetobacter diagnóza   mikrobiologie   MeSH
• limita detekce * MeSH
• RNA ribozomální 16S genetika   MeSH
• spektrometrie hmotnostní - ionizace laserem za účasti matrice přístrojové vybavení   metody   MeSH
• techniky typizace bakterií přístrojové vybavení   metody   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• RNA ribozomální 16S MeSH