Prostataerkrankungen: Ursachen und Behandlung
The epidemiology, Streptococcus oralis in der Prostata, and biology of nonencapsulated Streptococcus pneumoniae are largely unknown.
Increased colonization capacity and transformability are, however, intriguing features of these pneumococci and play an important role. Twenty-seven nonencapsulated pneumococci were identified in a nationwide collection of 1, nasopharyngeal samples and blood samples obtained between and On the basis of multilocus sequence typing and capsule region analysis we divided the nonencapsulated pneumococci into two groups.
Group I was closely related to encapsulated strains. Group II had a clonal population structure, including two geographically widespread clones able to cause epidemic conjunctivitis and invasive diseases. Group II strains also carried a 1,bp homologue of aliB aliB- like ORF 2 in the capsule region, which was highly homologous to a sequence in the capsule region of Streptococcus mitis.
A gene fragment homologous to capN Streptococcus oralis in der Prostata serotypes 33 and 37 suggests that group II strains were derived from encapsulated pneumococci some time ago. Therefore, loss of capsule expression in vivo was found to be associated with the importation of one or two aliB homologues in some nonencapsulated pneumococci. Streptococcus pneumoniae is an important human pathogen that causes meningitis, sepsis, pneumonia, and upper respiratory tract infections, such as acute otitis.
This gram-positive bacterium is usually surrounded by a polysaccharide capsule, which acts as a virulence factor by protecting the bacterium from phagocytosis. The capsule is the main target for protective antibodies, and pneumococcal strains are grouped into serotypes based on the antigenic properties of their capsules. The capsule is also the main target of currently used pneumococcal vaccines. Some S. Nonencapsulated strains are less virulent than encapsulated strains in a mouse model 12but nonencapsulated strains can also be responsible for disease, as described by Martin et al.
Little is known about the epidemiology and population genetics of nonencapsulated pneumococci. Whatmore et Streptococcus oralis in der Prostata. Nonencapsulated strains adhere better to respiratory epithelial cells and have an advantage when the nasopharynx is colonized 16 Streptococcus oralis in der Prostata, Also, the lack of a capsule makes them more transformable 20 Encapsulated pneumococci may therefore take advantage of down-regulation or transitory loss of capsule expression while they colonize the nasopharynx 25 A mechanism that has been shown to prevent capsule Streptococcus oralis in der Prostata in vitro is inactivation of capsule genes by duplications which can later be excised, causing reversion to the encapsulated phenotype 25 Also, a single mutation can lead to the loss of capsule expression for serotype 3 3.
In this paper we describe a novel finding. Loss of capsule expression in vivo was observed to be associated with the importation of an aliB homologue in some nonencapsulated pneumococci. The colonizing strains used for this study originated from a strain collection 1, isolates obtained from a nationwide surveillance for nasopharyngeal isolates of S.
The invasive strains of S. Isolates were serotyped by using the Quellung reaction with specific antisera from the Statens Serum Institute Copenhagen, Denmark. Strains which did not react with any of the pool sera were retyped after growth under anaerobic conditions to enhance capsule expression All nontypeable strains were sent to the Statens Serum Institute for retyping.
Chromosomal DNA were obtained from S. Southern blotting was performed essentially as described previously 21with the following exceptions. Probes were Streptococcus oralis in der Prostata nonradioactively by using the ECL direct nucleic acid labeling and detection system Amersham Biosciences, Duebendorf, Switzerland according to the manufacturer's instructions. The same system was used to detect signals. Schematic representation of cap regions of nonencapsulated S.
Cap regions i. For comparison, the cap region of a serotype 19F strain is shown at the top 9. Regions and ORFs found in nonencapsulated strains exhibiting high levels of homology to the cap region including dexB and aliA of encapsulated S.
The capN- like ORF of strain Regions with no homology to database entries are indicated by open boxes. Probes cap The cps19f gene 9 and the cap region of nonencapsulated strains are drawn to different scales; scale bars are indicated beneath the corresponding regions.
Amplification, sequencing, and analysis of the seven housekeeping genes were carried out as described previously 8. The entire cap region of strains The mixture was transferred to a 1. The PCR products were visualized in an agarose gel by staining with ethidium bromide. Northern blotting was performed by standard methods 21except that the nylon membrane was probed with a chemiluminescently labeled PCR product.
Labeling of the probe and visualization of the blot were performed Streptococcus oralis in der Prostata to the manufacturer's instructions ECL direct nucleic acid labeling and detection system; Amersham Biosciences.
Proteins were detected by using the Transcend chemiluminescent translation detection system Promega according to the manufacturer's instructions. The sizes of proteins were estimated by comparison with a prestained marker Bio-Rad Laboratories, Inc. Transformation of E. First, a 1,bp fragment of the dexB ORF of strain Downstream Streptococcus oralis in der Prostata cat a bp fragment of the capN- like ORF of strain The whole dexB-cat-capN construct 3. The dexB-cat-capN amplicon was then used to transform competent cells of S.
Recombinant clones were selected on CSBA plates containing 3 mg of chloramphenicol per liter. Appropriate dilutions were plated on CSBA plates for subsequent counting of colonies. A total of eight experiments were performed, and Streptococcus oralis in der Prostata strain was analyzed in triplicate in each experiment.
A total of 1, noninvasive and invasive S. Forty-five isolates 2. Of these 45 isolates, 27 1. Of the 27 truly nonencapsulated isolates, 7 were invasive and 20 Streptococcus oralis in der Prostata the nasopharynx. The 27 nonencapsulated strains were characterized by MLST. Three clusters were identified. Clone A strains were isolated from patients of different ages and from different geographical locations around Switzerland data not shown.
Of the 18 difficult-to-type isolates, all but three belonged to one of Streptococcus oralis in der Prostata clones data not shown which were eventually characterized as serotypes 1, 38, and 6A.
Southern blotting was performed by probing with PCR products representing a conserved region of the cap locus of a typical encapsulated serotype 19F strain, strain Probe cap This indicated that cap Streptococcus oralis in der Prostata were present and corresponded to the observation made by Arrecubieta et al.
Because of the apparent differences in the cap locus, sequence analysis Streptococcus oralis in der Prostata performed with three representative strains belonging to clone A and strain This analysis revealed high homology in this region for all four strains Fig. BLAST analysis revealed that capsule genes, which are usually found in encapsulated pneumococci, were absent, except for a region with homology to the capN gene of serotypes 33F and 37 However, we found two apparent ORFs which were 1, to 2, and 1, bp long, exhibited 61 to Strain In strains A Southern blot probed with cap B Probe cap The banding Streptococcus oralis in der Prostata for the nonencapsulated strains belonging to the clone A complex strains The banding patterns for the five encapsulated strains strains The banding patterns for nonencapsulated strains representing clone B strain Molecular weights were determined by using a standard run on the gel, which was visualized before blotting.
Characterization of the cap region Streptococcus oralis in der Prostata nonencapsulated pneumococcal isolates by Southern blotting, PCR, and sequencing analysis.
Having identified these novel ORFs in the cap locus, we used a Streptococcus oralis in der Prostata specific for aliB- like ORF 2 bp for Southern blotting of three clone A strains and all nontypeable strains not belonging to clone A.
This probe hybridized only to the isolates which failed to bind to probe cap Therefore, nontypeable strains could be divided into two groups. Group I Streptococcus oralis in der Prostata to have the conserved capsule gene region binding to probe cap All other nonencapsulated isolates either gave a nondetectable or weak amplification product.
The weak band was interpreted as a nonspecific band, since it was also observed for strain In addition, the hypothetical protein gene spradjacent to dexB in the capsule region of the S. Genes of S. However, the homology between the capsule regions of S. No transcription product was found for clone C isolates By using Northern blotting Fig. There was also a weak band of a similar size for encapsulated isolate There is a weak band for encapsulated serotype 19F control strain Streptococcus oralis in der Prostata In vitro translation produced a protein from the aliB -like ORF 1 region for all three nonencapsulated clone A strains tested strains The position of the protein standard was marked on the blot first and last lanes ; positive and negative controls were produced according to the instructions of the kit manufacturer.
In vitro translation assays showed that translation products for aliB- like ORF 1 were obtained from isolates The mean percentage of cells in the strain These nontypeable strains otherwise had the characteristics of typical S.