Geographic Distribution of Penicillin-Resistant Clones of Streptococcus pneumoniae: Characterization by Penicillin-Binding Protein Profile, Surface Protein A Typing, and Multilocus Enzyme Analysis

ABSTRACT Lactoferrin (Lf), an iron-sequestering glycoprotein, predominates in mucosal secretions, where the level of free extracellular iron (10−18 M) is not sufficient for bacterial growth. This represents a mechanism of resistance to bacterial infections by prevention of colonization of the host by pathogens. In this study we were able to show that Streptococcus pneumoniaespecifically recognizes and binds the iron carrier protein human Lf (hLf). Pretreatment of pneumococci with proteases reduced hLf binding significantly, indicating that the hLf receptor is proteinaceous. Binding assays performed with 63 clinical isolates belonging to different serotypes showed that 88% of the tested isolates interacted with hLf. Scatchard analysis showed the existence of two hLf-binding proteins with dissociation constants of 5.7 × 10−8and 2.74 × 10−7 M. The receptors were purified by affinity chromatography, and internal sequence analysis revealed that one of the S. pneumoniae proteins was homologous to pneumococcal surface protein A (PspA). The function of PspA as an hLf-binding protein was confirmed by the ability of purified PspA to bind hLf and to competitively inhibit hLf binding to pneumococci.S. pneumoniae may use the hLf-PspA interaction to overcome the iron limitation at mucosal surfaces, and this might represent a potential virulence mechanism.

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In Silico design of an epitope-based vaccine against Choline binding protein A of Streptococcus pneumoniae

Informatics in Medicine Unlocked ◽

10.1016/j.imu.2021.100546 ◽

2021 ◽

pp. 100546

Author(s):

Meherunnesa Munia ◽

Shafi Mahmud ◽

Mohammed Mohasin ◽

K.M.Kaderi Kibria

Keyword(s):

Streptococcus Pneumoniae ◽

In Silico ◽

Binding Protein ◽

Protein A ◽

In Silico Design

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Increasing Ceftriaxone Resistance and Multiple Alterations of Penicillin-Binding Proteins among Penicillin-Resistant Streptococcus pneumoniae Isolates in Taiwan

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.01563-06 ◽

2007 ◽

Vol 51 (9) ◽

pp. 3404-3406 ◽

Cited By ~ 20

Author(s):

Cheng-Hsun Chiu ◽

Lin-Hui Su ◽

Yhu-Chering Huang ◽

Jui-Chia Lai ◽

Hsiu-Ling Chen ◽

...

Keyword(s):

Streptococcus Pneumoniae ◽

Amino Acid ◽

Binding Proteins ◽

Binding Protein ◽

Penicillin Binding Protein ◽

Penicillin Binding Proteins

ABSTRACT The rate of nonsusceptibility of penicillin-resistant Streptococcus pneumoniae strains to ceftriaxone increased significantly in Taiwan in 2005. Approximately 90% of the ceftriaxone-nonsusceptible isolates were found to be of four major serotypes (serotypes 6B, 14, 19F, and 23F). Seven amino acid alterations in the penicillin-binding protein 2B transpeptidase-encoding region specifically contributed to the resistance.

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Mosaic-Like Structure of Penicillin-Binding Protein 2 Gene (penA) in Clinical Isolates of Neisseria gonorrhoeae with Reduced Susceptibility to Cefixime

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.46.12.3744-3749.2002 ◽

2002 ◽

Vol 46 (12) ◽

pp. 3744-3749 ◽

Cited By ~ 132

Author(s):

Satoshi Ameyama ◽

Shoichi Onodera ◽

Masahiro Takahata ◽

Shinzaburo Minami ◽

Nobuko Maki ◽

...

Keyword(s):

Streptococcus Pneumoniae ◽

Neisseria Gonorrhoeae ◽

Neisseria Meningitidis ◽

Binding Protein ◽

Clinical Isolates ◽

Penicillin Binding Protein ◽

Gene Sequences ◽

Neisseria Flavescens ◽

Neisseria Perflava

ABSTRACT Neisseria gonorrhoeae strains with reduced susceptibility to cefixime (MICs, 0.25 to 0.5 μg/ml) were isolated from male urethritis patients in Tokyo, Japan, in 2000 and 2001. The resistance to cephems including cefixime and penicillin was transferred to a susceptible recipient, N. gonorrhoeae ATCC 19424, by transformation of the penicillin-binding protein 2 gene (penA) that had been amplified by PCR from a strain with reduced susceptibility to cefixime (MIC, 0.5 μg/ml). The sequences of penA in the strains with reduced susceptibilities to cefixime were different from those of other susceptible isolates and did not correspond to the reported N. gonorrhoeae penA gene sequences. Some regions in the transpeptidase-encoding domain in this penA gene were similar to those in the penA genes of Neisseria perflava (N. sicca), Neisseria cinerea, Neisseria flavescens, and Neisseria meningitidis. These results showed that a mosaic-like structure in the penA gene conferred reductions in the levels of susceptibility of N. gonorrhoeae to cephems and penicillin in a manner similar to that found for N. meningitidis and Streptococcus pneumoniae.

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DNA vaccines expressing pneumococcal surface protein A (PspA) elicit protection levels comparable to recombinant protein

Journal of Medical Microbiology ◽

10.1099/jmm.0.46217-0 ◽

2006 ◽

Vol 55 (4) ◽

pp. 375-378 ◽

Cited By ~ 14

Author(s):

Daniela M. Ferreira ◽

Eliane N. Miyaji ◽

Maria Leonor S. Oliveira ◽

Michelle Darrieux ◽

Ana Paula M. Arêas ◽

...

Keyword(s):

Streptococcus Pneumoniae ◽

Recombinant Protein ◽

Dna Vaccines ◽

Protein A ◽

Surface Protein ◽

Humoral Response ◽

Cost Effective ◽

Promising Candidate ◽

Pneumococcal Surface Protein A ◽

Antibody Levels

Pneumococcal surface protein A (PspA) is a promising candidate for the development of cost-effective vaccines against Streptococcus pneumoniae. In the present study, BALB/c mice were immunized with DNA vaccine vectors expressing the N-terminal region of PspA. Animals immunized with a vector expressing secreted PspA developed higher levels of antibody than mice immunized with the vector expressing the antigen in the cytosol. However, both immunogens elicited similar levels of protection against intraperitoneal challenge. Furthermore, immunization with exactly the same fragment in the form of a recombinant protein, with aluminium hydroxide as an adjuvant, elicited even higher antibody levels, but this increased humoral response did not correlate with enhanced protection. These results show that DNA vaccines expressing PspA are able to elicit protection levels comparable to recombinant protein, even though total anti-PspA IgG response is considerably lower.

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