influenzae rd kw20  (ATCC)

Journal: Antimicrobial Agents and Chemotherapy

Article Title: Evolution of beta-lactam resistance causes fitness reductions and several cases of collateral sensitivities in the human pathogen Haemophilus influenzae

doi: 10.1128/aac.00576-25

Figure Lengend Snippet: Increasing number of mutations and changes in beta-lactam minimum inhibitory concentrations (MICs) in six evolution experiments. Number of mutations (black) and minimum inhibitory concentration fold increase compared to the parental strain Rd KW20 for ampicillin (Amp, red), cefotaxime (Ctx, green), and ceftriaxone (Cro, blue) in selected clones over 20 passages (two or five clones per passage). Bacterial population ( A ) without antibiotic exposure and exposed to increasing concentrations of ( B ) ampicillin, ( C ) cefotaxime, ( D ) ceftriaxone replicate 1, ( E ) ceftriaxone replicate 2, and ( F ) ceftriaxone replicate 3. Shaded areas represent the 95% confidence interval.

Article Snippet: Briefly, short reads were mapped to the reference genome H. influenzae Rd KW20 (American Type Culture Collection 51907) (BioSample SAMN39831887 ) using the Burrows–Wheeler Aligner (BWA) , and allele calling was done with the Genome Analysis Toolkit ( ).

Techniques: Concentration Assay, Clone Assay

Journal: Antimicrobial Agents and Chemotherapy

Article Title: Evolution of beta-lactam resistance causes fitness reductions and several cases of collateral sensitivities in the human pathogen Haemophilus influenzae

doi: 10.1128/aac.00576-25

Figure Lengend Snippet: Maximum likelihood phylogeny of H. influenzae Rd KW20 clones evolved in the presence of ampicillin ( A , 53 clones), cefotaxime ( B , 56 clones), and ceftriaxone ( C , 57 clones). Amino acid substitutions in the penicillin-binding protein 3 (PBP3) and presence of mutations in specified genes as well as minimum inhibitory concentration (MIC) changes over time are color coded. Strains that exceeded the clinical breakpoint for ampicillin/cefotaxime/ceftriaxone according to EUCAST breakpoints are marked with a white star at the MIC heatmap. The specified genes are those in which at least 20 clones from the whole set of selected clones exhibited mutations but did not mutate under antibiotic-free conditions.

Article Snippet: Briefly, short reads were mapped to the reference genome H. influenzae Rd KW20 (American Type Culture Collection 51907) (BioSample SAMN39831887 ) using the Burrows–Wheeler Aligner (BWA) , and allele calling was done with the Genome Analysis Toolkit ( ).

Techniques: Clone Assay, Binding Assay, Concentration Assay

Journal: Antimicrobial Agents and Chemotherapy

Article Title: Evolution of beta-lactam resistance causes fitness reductions and several cases of collateral sensitivities in the human pathogen Haemophilus influenzae

doi: 10.1128/aac.00576-25

Figure Lengend Snippet: Crystal structure of transpeptidase domain (residues 254–610) of the penicillin-binding protein 3 (PBP3) of H. influenzae with superimposed ampicillin ( A , colored in cyan) and cefotaxime ( B , magenta) molecules. In vitro selected amino acid substitutions in PBP3 Thr332lle, Thr443Ala, Ala530Ser, Asp551Tyr, and Ala561Glu are in red. Known positions for amino acid substitutions defining established PBP3 resistance groups are in green.

Article Snippet: Briefly, short reads were mapped to the reference genome H. influenzae Rd KW20 (American Type Culture Collection 51907) (BioSample SAMN39831887 ) using the Burrows–Wheeler Aligner (BWA) , and allele calling was done with the Genome Analysis Toolkit ( ).

Techniques: Binding Assay, In Vitro

Journal: Antimicrobial Agents and Chemotherapy

Article Title: Evolution of beta-lactam resistance causes fitness reductions and several cases of collateral sensitivities in the human pathogen Haemophilus influenzae

doi: 10.1128/aac.00576-25

Figure Lengend Snippet: Bacterial fitness of selected clones derived from evolving populations exposed to ampicillin (Amp), cefotaxime (Ctx), and ceftriaxone (Cro). Bacterial fitness measured as relative growth difference between the ancestral strain ( H. influenzae Rd KW20) and the selected clone. A relative fitness of 1 indicates no fitness cost, whereas a value greater or less than 1 indicates increased or decreased fitness, respectively. The black bars represent standard deviations. * P adj < 0.05, ** P adj < 0.01, *** P adj < 0.001. The heatmap indicates MIC values of Amp, Ctx, and Cro (in mg/L) of the respective strain (already presented in ). Stars indicate clinical resistance above the respective EUCAST breakpoints. Hatched panels indicate phenotypic heterogeneity. Clones that were derived from the same evolution experiment are grouped together on the y -axis.

Article Snippet: Briefly, short reads were mapped to the reference genome H. influenzae Rd KW20 (American Type Culture Collection 51907) (BioSample SAMN39831887 ) using the Burrows–Wheeler Aligner (BWA) , and allele calling was done with the Genome Analysis Toolkit ( ).

Techniques: Clone Assay, Derivative Assay

Journal: Antimicrobial Agents and Chemotherapy

Article Title: Evolution of beta-lactam resistance causes fitness reductions and several cases of collateral sensitivities in the human pathogen Haemophilus influenzae

doi: 10.1128/aac.00576-25

Figure Lengend Snippet: Collateral effects of increased MICs against individual beta-lactam antibiotics. Heat map of log 2 -transformed relative increase in MIC of ampicillin, cefotaxime, ceftriaxone (underlying MIC values already presented in ), meropenem (beta-lactams), amikacin, kanamycin, gentamicin (aminoglycosides), levofloxacin, moxifloxacin (fluoroquinolones), clarithromycin (macrolide), vancomycin (glycopeptide), rifampicin (ansamycin), colistin (polymyxin), and tetracycline (tetracycline) in mutant clones relative to the MIC of the parental strain H. influenzae Rd KW20. Selected clones were evolved in the multi-step evolution experiment. Stars indicate clinical resistance above the respective EUCAST breakpoints (not available for aminoglycosides, clarithromycin, vancomycin, and colistin). Hatched panels indicate phenotypic heterogeneity. Clones that were derived from the same evolution experiment are grouped together on the y -axis.

Article Snippet: Briefly, short reads were mapped to the reference genome H. influenzae Rd KW20 (American Type Culture Collection 51907) (BioSample SAMN39831887 ) using the Burrows–Wheeler Aligner (BWA) , and allele calling was done with the Genome Analysis Toolkit ( ).

Techniques: Transformation Assay, Glycoproteomics, Mutagenesis, Clone Assay, Derivative Assay