O-Antigen Diversity among
            <i>Acinetobacter baumannii</i>
            Strains from the Czech Republic and Northwestern Europe, as Determined by Lipopolysaccharide-Specific Monoclonal Antibodies

Pantophlet, Ralph; Nemec, Alexandr; Brade, Lore; Brade, Helmut; Dijkshoorn, Lenie

doi:10.1128/jcm.39.7.2576-2580.2001

Cited by 19 publications

(8 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…ST15 is phylogenetically linked with European hospital clone I (15,35), which is associated with epidemic behavior and multidrug resistance (31,35,47). Although at least 39 sequence types of A. baumannii were distinguished among the military outbreak strains (15), four of them (ST11, ST14, ST16, and ST10) accounted for over half of the isolates, suggesting either that the outbreak was clonal in nature or that particular sequence types of A. baumannii are more likely to cause human infection.…”

Section: Discussionmentioning

confidence: 99%

Identification and Characterization of an Acinetobacter baumannii Biofilm-Associated Protein

Luke²,

2008

View full text Add to dashboard Cite

We have identified a homologue to the staphylococcal biofilm-associated protein (Bap) in a bloodstream isolate of Acinetobacter baumannii. The fully sequenced open reading frame is 25,863 bp and encodes a protein with a predicted molecular mass of 854 kDa. Analysis of the nucleotide sequence reveals a repetitive structure consistent with bacterial cell surface adhesins. Bap-specific monoclonal antibody (MAb) 6E3 was generated to an epitope conserved among 41% of A. baumannii strains isolated during a recent outbreak in the U.S. military health care system. Flow cytometry confirms that the MAb 6E3 epitope is surface exposed. Random transposon mutagenesis was used to generate A. baumannii bap1302::EZ-Tn5, a mutant negative for surface reactivity to MAb 6E3 in which the transposon disrupts the coding sequence of bap. Time course confocal laser scanning microscopy and three-dimensional image analysis of actively growing biofilms demonstrates that this mutant is unable to sustain biofilm thickness and volume, suggesting a role for Bap in supporting the development of the mature biofilm structure. This is the first identification of a specific cell surface protein directly involved in biofilm formation by A. baumannii and suggests that Bap is involved in intercellular adhesion within the mature biofilm.

show abstract

Section: Discussionmentioning

confidence: 99%

Identification and Characterization of an Acinetobacter baumannii Biofilm-Associated Protein

Luke²,

2008

View full text Add to dashboard Cite

show abstract

“…These studies demonstrated that the A. baumannii OAg region is highly heterogeneous as numerous LPS glycoforms have been defined using both structural and antibody-based studies (21,(26)(27)(28)(41)(42)(43)(44). Although the structural analyses of A. baumannii LPS determined that this organism expresses an S-form LPS, phenotypic analyses of the molecules has been challenging because the OAg cannot be visualized following gel electrophoresis.…”

mentioning

confidence: 99%

Identification and Characterization of a Glycosyltransferase Involved in Acinetobacter baumannii Lipopolysaccharide Core Biosynthesis

Sauberan²,

et al. 2010

View full text Add to dashboard Cite

Although Acinetobacter baumannii has emerged as a significant cause of nosocomial infections worldwide, there have been few investigations describing the factors important for A. baumannii persistence and pathogenesis. This paper describes the first reported identification of a glycosyltransferase, LpsB, involved in lipopolysaccharide (LPS) biosynthesis in A. baumannii. Mutational, structural, and complementation analyses indicated that LpsB is a core oligosaccharide glycosyl transferase. Using a genetic approach, lpsB was compared with the lpsB homologues of several A. baumannii strains. These analyses indicated that LpsB is highly conserved among A. baumannii isolates. Furthermore, we developed a monoclonal antibody, monoclonal antibody 13C11, which reacts to an LPS core epitope expressed by approximately one-third of the A. baumannii clinical isolates evaluated to date. Previous studies describing the heterogeneity of A. baumannii LPS were limited primarily to structural analyses; therefore, studies evaluating the correlation between these surface glycolipids and pathogenesis were warranted. Our data from an evaluation of LpsB mutant 307::TN17, which expresses a deeply truncated LPS glycoform consisting of only two 3-deoxy-D-manno-octulosonic acid residues and lipid A, suggest that A. baumannii LPS is important for resistance to normal human serum and confers a competitive advantage for survival in vivo. These results have important implications for the role of LPS in A. baumannii infections.

show abstract

“…This will enable us to provide a complete O-serotyping scheme for these species, as has been successfully established for many other clinically significant gram-negative bacteria. Moreover, as has been reported in a recent study (27), such MAbs also have the potential to be employed as a means to define the prevalence of Acinetobacter serotypes in clinical settings and for the facile tracing of strains causing outbreaks in hospitals.…”

Section: Discussionmentioning

confidence: 89%

“…Due to the increased importance of Acinetobacter in the clinical environment and the lack of a reliable phenotypic method for the unambiguous identification of all members of the genus to the species level, we have focused on the development of an O-serotype-based identification scheme for Acinetobacter. Ongoing studies (22)(23)(24)(25)(26)(27) have been centered mainly on the generation of O-antigen-specific monoclonal antibodies (MAbs) against strains belonging to the A. calcoaceticus-A. baumannii complex, but to date, these antibodies have been tested only on small numbers of clinical isolates within a limited geographical range.…”

mentioning

confidence: 99%

Identification ofAcinetobacterIsolates from Species Belonging to theAcinetobacter calcoaceticus-Acinetobacter baumanniiComplex with Monoclonal Antibodies Specific for O Antigens of Their Lipopolysaccharides

Pantophlet

Severin

Nemec

et al. 2002

Clin Vaccine Immunol

Self Cite

View full text Add to dashboard Cite

The unambiguous identification of Acinetobacter strains, particularly those belonging to the Acinetobacter calcoaceticus-Acinetobacter baumannii complex, is often hindered by their close geno-and phenotypic relationships. In this study, monoclonal antibodies (MAbs) against the O antigens of the lipopolysaccharides from strains belonging to the A. calcoaceticus-A. baumannii complex were generated after the immunization of mice with heat-killed bacteria and shown by enzyme immunoassays and Western blotting to be specific for their homologous antigens. Since the A. calcoaceticus-A. baumannii complex comprises the most clinically relevant species, the MAbs were subsequently tested in dot and Western blots with proteinase K-treated lysates from a large collection of Acinetobacter isolates (n ‫؍‬ 631) to determine whether the antibodies could be used for the reliable identification of strains from this complex. Reactivity was observed with 273 of the 504 isolates (54%) from the A. calcoaceticus-A. baumannii complex which were included in this study. Isolates which reacted positively did so with only one antibody; no reactivity was observed with isolates not belonging to the A. calcoaceticus-A. baumannii complex (n ‫؍‬ 127). To identify additional putative O serotypes, isolates from the A. calcoaceticus-A. baumannii complex which showed no MAb reactivity were subjected to a method that enables the detection of lipid A moieties in lipopolysaccharides with a specific MAb on Western blots following acidic treatment of the membrane. By this method, additional serotypes were indeed identified, thus indicating which strains to select for future immunizations. This study contributes to the completion of a serotype-based identification scheme for Acinetobacter species, in particular, those which are presently of the most clinical importance.Acinetobacter spp. have gained increased recognition in recent years as pathogens which have the potential to cause severe nosocomial infections in critically ill patients (1, 33). However, the quick and reliable identification of Acinetobacter strains has been hampered for a number of years due to the close pheno-and genotypic relatedness of some species within the genus, particularly those of clinical relevance (1, 8). Based on DNA homology studies, 23 DNA groups (genomic species) are currently delineated, nine of which have received formal species names (3,4,12,20,32). Strains from genomic species 2 (Acinetobacter baumannii), 3, and 13 sensu Tjernberg and Ursing (13TU) (32) are frequently isolated from clinical specimens and are often associated with nosocomial outbreaks (1, 33); they belong, together with genomic species 1 (Acinetobacter calcoaceticus), to the so-called A. calcoaceticus-A. baumannii complex (11, 13). A. calcoaceticus strains are seldom isolated from patients or associated with infections (1). Other Acinetobacter strains are also isolated infrequently from patients, although both Acinetobacter junii and Acinetobacter johnsonii have been reported to be involved in cases o...

show abstract

O-Antigen Diversity among Acinetobacter baumannii Strains from the Czech Republic and Northwestern Europe, as Determined by Lipopolysaccharide-Specific Monoclonal Antibodies

Cited by 19 publications

References 18 publications

Identification and Characterization of an Acinetobacter baumannii Biofilm-Associated Protein

Identification and Characterization of an Acinetobacter baumannii Biofilm-Associated Protein

Identification and Characterization of a Glycosyltransferase Involved in Acinetobacter baumannii Lipopolysaccharide Core Biosynthesis

Identification ofAcinetobacterIsolates from Species Belonging to theAcinetobacter calcoaceticus-Acinetobacter baumanniiComplex with Monoclonal Antibodies Specific for O Antigens of Their Lipopolysaccharides

Contact Info

Product

Resources

About