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BMC Infectious Diseases May 2022The bacterial genus Aggregatibacter was categorized in 2006 to accommodate the former Actinobacillus actinomycetemcomitans, Haemophilus aphrophilus, and H. segnis...
BACKGROUND
The bacterial genus Aggregatibacter was categorized in 2006 to accommodate the former Actinobacillus actinomycetemcomitans, Haemophilus aphrophilus, and H. segnis species. Aggregatibacter kilianii is a normal resident of the human upper respiratory tract but can also cause serious infections. A. kilianii is relatively newly identified and has been isolated from conjunctivitis, wounds, abdominal abscesses, and blood.
CASE PRESENTATION
An 80-year-old female patient with distal common bile duct cancer was admitted to our hospital with sudden loss of consciousness and general weakness, fever, and abdominal pain for 3 days. Two colonial morphologies were isolated from both the blood and bile cultures; one was identified as Streptococcus constellatus subsp. pharyngis, but the other was not recognized by Vitek2 and MALDI-TOF. The 16 S rRNA sequences showed 99.73% similarity with the sequence of A. kilianii strains.
CONCLUSION AND DISCUSSION
This article presents the first case of a clinical isolate of A. kilianii outside Europe. This case is also the first of the antimicrobial profile of this strain. This report highlights the importance of proper molecular identification for timely diagnosis and treatment of disease.
Topics: Aged, 80 and over; Aggregatibacter; Aggregatibacter aphrophilus; Female; Humans; Streptococcus
PubMed: 35619055
DOI: 10.1186/s12879-022-07471-7 -
BMC Biochemistry Nov 2011The Gram-negative bacterium Haemophilus influenzae is a glutathione auxotroph and acquires the redox-active tripeptide by import. The dedicated glutathione transporter...
BACKGROUND
The Gram-negative bacterium Haemophilus influenzae is a glutathione auxotroph and acquires the redox-active tripeptide by import. The dedicated glutathione transporter belongs to the ATP-binding cassette (ABC)-transporter superfamily and displays more than 60% overall sequence identity with the well-studied dipeptide (Dpp) permease of Escherichia coli. The solute binding protein (SBP) that mediates glutathione transport in H. influenzae is a lipoprotein termed GbpA and is 54% identical to E. coli DppA, a well-studied member of family 5 SBP's. The discovery linking GbpA to glutathione import came rather unexpectedly as this import-priming SBP was previously annotated as a heme-binding protein (HbpA), and was thought to mediate heme acquisition. Nonetheless, although many SBP's have been implicated in more than one function, a prominent physiological role for GbpA and its partner permease in heme acquisition appears to be very unlikely. Here, we sought to characterize five representative GbpA homologs in an effort to delineate the novel GbpA-family of glutathione-specific family 5 SBPs and to further clarify their functional role in terms of ligand preferences.
RESULTS
Lipoprotein and non-lipoprotein GbpA homologs were expressed in soluble form and substrate specificity was evaluated via a number of ligand binding assays. A physiologically insignificant affinity for hemin was observed for all five GbpA homologous test proteins. Three out of five test proteins were found to bind glutathione and some of its physiologically relevant derivatives with low- or submicromolar affinity. None of the tested SBP family 5 allocrites interacted with the remaining two GbpA test proteins. Structure-based sequence alignments and phylogenetic analysis show that the two binding-inert GbpA homologs clearly form a separate phylogenetic cluster. To elucidate a structure-function rationale for this phylogenetic differentiation, we determined the crystal structure of one of the GbpA family outliers from H. parasuis. Comparisons thereof with the previously determined structure of GbpA in complex with oxidized glutathione reveals the structural basis for the lack of allocrite binding capacity, thereby explaining the outlier behavior.
CONCLUSIONS
Taken together, our studies provide for the first time a collective functional look on a novel, Pasteurellaceae-specific, SBP subfamily of glutathione binding proteins, which we now term GbpA proteins. Our studies strongly implicate GbpA family SBPs in the priming step of ABC-transporter-mediated translocation of useful forms of glutathione across the inner membrane, and rule out a general role for GbpA proteins in heme acquisition.
Topics: Amino Acid Sequence; Bacteria; Bacterial Proteins; Glutathione; Membrane Transport Proteins; Molecular Sequence Data; Pasteurellaceae; Phylogeny; Sequence Alignment; Species Specificity
PubMed: 22087650
DOI: 10.1186/1471-2091-12-59 -
Brazilian Journal of Microbiology :... 2018Histophilus somni is a Gram-negative bacterium that is associated with a disease complex (termed histophilosis) that can produce several clinical syndromes predominantly...
Histophilus somni is a Gram-negative bacterium that is associated with a disease complex (termed histophilosis) that can produce several clinical syndromes predominantly in cattle, but also in sheep. Histophilosis is well described in North America, Canada, and in some European countries. In Brazil, histophilosis has been described in cattle with respiratory, reproductive, and systemic disease, with only one case described in sheep. This report describes the occurrence of Histophilus somni-associated disease in sheep from Southern Brazil. Eight sheep with different clinical manifestations from five farms were investigated by a combination of pathological and molecular diagnostic methods to identify additional cases of histophilosis in sheep from Brazil. The principal pathological lesions were thrombotic meningoencephalitis, fibrinous bronchopneumonia, pulmonary abscesses, and necrotizing myocarditis. The main clinical syndromes associated with H. somni were thrombotic meningoencephalitis (n=4), septicemia (n=4), bronchopneumonia (n=4), and myocarditis (n=3). H. somni DNA was amplified from multiple tissues of all sheep with clinical syndromes of histophilosis; sequencing confirmed the PCR results. Further, PCR assays to detect Pasteurella multocida and Mannheimia haemolytica were negative. These findings confirmed the participation of H. somni in the clinical syndromes investigated during this study, and adds to the previous report of histophilosis in sheep from Brazil.
Topics: Animals; Brazil; Mannheimia haemolytica; Pasteurellaceae Infections; Polymerase Chain Reaction; Sheep; Sheep Diseases
PubMed: 29551641
DOI: 10.1016/j.bjm.2017.12.008 -
Journal of Clinical Pathology Jul 1969Haemophilus aphrophilus was isolated from the blood of a 31-year-old man with subacute bacterial endocarditis. Subsequently the patient died with acute tubular necrosis...
Haemophilus aphrophilus was isolated from the blood of a 31-year-old man with subacute bacterial endocarditis. Subsequently the patient died with acute tubular necrosis of the kidney, probably secondary to cardiac failure. The characteristics of the species are described and pathogenicity to mice is reported for the first time.
Topics: Acute Kidney Injury; Adult; Animals; Endocarditis, Subacute Bacterial; Haemophilus; Haemophilus Infections; Heart Failure; Humans; Male; Mice
PubMed: 5798638
DOI: 10.1136/jcp.22.4.486 -
Antonie Van Leeuwenhoek Apr 2014Polyphasic analysis was done on 24 strains of Bisgaard taxon 16 from five European countries and mainly isolated from dogs and human dog-bite wounds. The isolates...
Polyphasic analysis was done on 24 strains of Bisgaard taxon 16 from five European countries and mainly isolated from dogs and human dog-bite wounds. The isolates represented a phenotypically and genetically homogenous group within the family Pasteurellaceae. Their phenotypic profile was similar to members of the genus Pasteurella. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry clearly identified taxon 16 and separated it from all other genera of Pasteurellaceae showing a characteristic peak combination. Taxon 16 can be further separated and identified by a RecN protein signature sequence detectable by a specific PCR. In all phylogenetic analyses based on 16S rRNA, rpoB, infB and recN genes, taxon 16 formed a monophyletic branch with intraspecies sequence similarity of at least 99.1, 90.8, 96.8 and 97.2 %, respectively. Taxon 16 showed closest genetic relationship with Bibersteinia trehalosi as to the 16S rRNA gene (95.9 %), the rpoB (89.8 %) and the recN (74.4 %), and with Actinobacillus lignieresii for infB (84.9 %). Predicted genome similarity values based on the recN gene sequences between taxon 16 isolates and the type strains of known genera of Pasteurellaceae were below the genus level. Major whole cell fatty acids for the strain HPA 21(T) are C14:0, C16:0, C18:0 and C16:1 ω7c/C15:0 iso 2OH. Major respiratory quinones are menaquinone-8, ubiquinone-8 and demethylmenaquinone-8. We propose to classify these organisms as a novel genus and species within the family of Pasteurellaceae named Frederiksenia canicola gen. nov., sp. nov. The type strain is HPA 21(T) (= CCUG 62410(T) = DSM 25797(T)).
Topics: Animals; Bacterial Proteins; Bacterial Typing Techniques; Bites and Stings; Cluster Analysis; DNA Restriction Enzymes; DNA, Bacterial; DNA, Ribosomal; DNA-Directed RNA Polymerases; Dogs; Europe; Fatty Acids; Humans; Molecular Sequence Data; Pasteurellaceae; Phylogeny; Prokaryotic Initiation Factor-2; Quinones; RNA, Ribosomal, 16S; Sequence Analysis, DNA; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; Wounds and Injuries
PubMed: 24510449
DOI: 10.1007/s10482-014-0129-0 -
Journal of the American Association For... Jul 2019The uncertain taxonomy of [] and other rodent has hindered the acquisition of knowledge on the biology and disease for this group of bacteria. Recently, these...
The uncertain taxonomy of [] and other rodent has hindered the acquisition of knowledge on the biology and disease for this group of bacteria. Recently, these organisms have been reclassified within the new genus In this study, we documented which of the new described spp. are present in the mouse and rat microbiologic units of an experimental facility. Screening all of the microbiologic units populated with mice and rats yielded 51 isolates. Molecular and phenotypic diagnosis indicated the colonization of mice by and , whereas and were found in rats. Overall, we document the association of laboratory rodents with 3 of the newly described . Diagnostics of the spp. at the species level can decisively contribute to the progress of knowledge on these bacteria.
Topics: Animals; Laboratory Animal Science; Mice; Pasteurellaceae; Pasteurellaceae Infections; Rats; Rodent Diseases
PubMed: 31239009
DOI: 10.30802/AALAS-JAALAS-19-000001 -
Journal of Bacteriology Jun 2020The bacterial bipartite transferrin receptor is an iron acquisition system that several important human and animal pathogens require for survival. It consists of the...
The bacterial bipartite transferrin receptor is an iron acquisition system that several important human and animal pathogens require for survival. It consists of the TonB-dependent transporter transferrin binding protein A (TbpA) and the surface lipoprotein transferrin binding protein B (TbpB). Curiously, the Tbps are only found in host-specific pathogens and are themselves host specific, meaning that they will bind to the transferrin of their host species but not to the transferrins of other animal species. While this phenomenon has long been established, neither the steps in the evolutionary process that led to this exquisite adaptation for the host nor the steps that could alter it are known. We sought to gain insight into these processes by studying Tbp specificity in , an economically important pathogen of cattle. A past study showed that whole cells of specifically bind bovine transferrin but not transferrin from sheep and goats, two bovids whose transferrins share 93% amino acid sequence identity with bovine transferrin. To our surprise, we found that can use sheep and goat transferrins as iron sources for growth and that TbpB, but not TbpA, has detectable affinity for sheep and goat transferrins. Furthermore, a third transferrin binding protein found in , TbpA2, also showed affinity for sheep and goat transferrins. Our results suggest that TbpB and TbpA2 may contribute to broadening the host transferrin recognition range of Host-restricted pathogens infect a single host species or a narrow range of host species. , a pathogen that incurs severe economic losses for the cattle industry, infects cattle, sheep, and goats but not other mammals. The transferrin binding proteins, TbpA and TbpB, are thought to be a key iron acquisition system in ; however, despite their importance, TbpA and TbpB were previously shown to be cattle transferrin specific. In our study, we find that TbpB and another little-studied Tbp, TbpA2, bind sheep and goat transferrins, as well as bovine transferrin. Our results suggest that TbpB and TbpA2 may allow for host range expansion and provide a mechanism for how host specificity in Tbp-encoding pathogens can be altered.
Topics: Amino Acid Sequence; Animals; Bacterial Proteins; Cattle; Cattle Diseases; Goats; Humans; Pasteurellaceae; Pasteurellaceae Infections; Protein Binding; Sequence Alignment; Sheep; Transferrin; Transferrin-Binding Protein A; Transferrin-Binding Protein B
PubMed: 32366593
DOI: 10.1128/JB.00177-20 -
Scientific Reports Dec 2019Respiratory tract infections are a major health problem and indication for antimicrobial use in cattle and in humans. Currently, most antimicrobial treatments are...
Respiratory tract infections are a major health problem and indication for antimicrobial use in cattle and in humans. Currently, most antimicrobial treatments are initiated without microbiological results, holding the risk of inappropriate first intention treatment. The main reason for this empirical treatment is the long turnaround time between sampling and availability of identification and susceptibility results. Therefore the objective of the present study was to develop a rapid identification procedure for pathogenic respiratory bacteria in bronchoalveolar lavage fluid (BALf) samples from cattle by MALDI-TOF MS, omitting the cultivation step on agar plates to reduce the turnaround time between sampling and identification of pathogens. The effects of two different liquid growth media and various concentrations of bacitracin were determined to allow optimal growth of Pasteurellaceae and minimise contamination. The best procedure was validated on 100 clinical BALf samples from cattle with conventional bacterial culture as reference test. A correct identification was obtained in 73% of the samples, with 59.1% sensitivity (Se) (47.2-71.0%) and 100% specificity (Sp) (100-100%) after only 6 hours of incubation. For pure and dominant culture samples, the procedure was able to correctly identify 79.2% of the pathogens, with a sensitivity (Se) of 60.5% (45.0-76.1%) and specificity (Sp) of 100% (100-100%). In mixed culture samples, containing ≥2 clinically relevant pathogens, one pathogen could be correctly identified in 57% of the samples with 57.1% Se (38.8-75.5%) and 100% Sp (100-100%). In conclusion, MALDI-TOF MS is a promising tool for rapid pathogen identification in BALf. This new technique drastically reduces turnaround time and may be a valuable decision support tool to rationalize antimicrobial use.
Topics: Animals; Bacterial Typing Techniques; Bronchoalveolar Lavage Fluid; Cattle; Cattle Diseases; Humans; Mannheimia haemolytica; Moraxella; Moraxellaceae Infections; Pasteurella Infections; Pasteurella multocida; Pasteurellaceae; Pasteurellaceae Infections; Respiratory Tract Infections; Sensitivity and Specificity; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
PubMed: 31804604
DOI: 10.1038/s41598-019-54599-9 -
Experimental Animals Jan 2008To investigate the pathogenicities of P. pneumotropica (Pp) and V-factor dependent Pasteurellaceae (VFDP) in immunodeficient rats, experimental infections of F344-rnu...
To investigate the pathogenicities of P. pneumotropica (Pp) and V-factor dependent Pasteurellaceae (VFDP) in immunodeficient rats, experimental infections of F344-rnu rats were performed using 3 strains (ATCC 35149, CNP 160 and RPZ) of Pp and 4 strains (V6, V7, V8 and V9) of VFDP. Four animals per experimental group were inoculated twice on day 0 and post-inoculation day (PID) 14 with bacterial suspension intranasally. Two animals from each group were sacrificed on PID 60 and 120, and examined. In the animals inoculated with strains of Pp, sneezing was observed in some animals inoculated with strains ATCC 35149 and CNP 160 until PID 31. No clinical signs were observed in other animals. The strains were mainly isolated from the nasal cavity and trachea on PID 60, and the nasal cavity, trachea and lung on PID 120. Inflammation and necrosis of nasal cavity mucosa were observed in all animals inoculated with strains ATCC 35149 and CNP 160 in a histopathologic examination. No histopathological changes were observed in any other animal. In the animals inoculated with strains of VFDP, neither clinical disorder nor histopathological change was observed. The strains were mainly isolated from the trachea on PID 60, and from the trachea and lungs on PID 120. From these results, the pathogenicity of Pp in immunodeficient rats appears to differ by strain, and VFDP appears to be non-pathogenic in immunodeficient rats.
Topics: Animals; Female; Immunologic Deficiency Syndromes; Pasteurella pneumotropica; Pasteurellaceae; Pasteurellaceae Infections; Rats; Rats, Inbred F344; Rats, Mutant Strains; Rodent Diseases
PubMed: 18256519
DOI: 10.1538/expanim.57.57 -
Infection and Immunity Jan 2021-Ribosylhomocysteinase (LuxS) is required for the synthesis of the autoinducer-2 (AI-2) quorum-sensing signaling molecule in many Gram-negative bacteria. The bovine (and... (Comparative Study)
Comparative Study
-Ribosylhomocysteinase (LuxS) is required for the synthesis of the autoinducer-2 (AI-2) quorum-sensing signaling molecule in many Gram-negative bacteria. The bovine (and ovine) opportunistic pathogen contains and forms a biofilm containing an exopolysaccharide (EPS) in the matrix. Since biofilm formation is regulated by quorum sensing in many bacteria, the roles of in virulence and biofilm formation were investigated. Although culture supernatants from were ineffective at inducing bioluminescence in the reporter strain BB170, complemented the biosynthesis of AI-2 in the -deficient strain DH5α. strain 2336 was inactivated by transposon mutagenesis. RNA expression profiles revealed that many genes were significantly differentially expressed in the mutant compared to that in the wild-type, whether the bacteria were grown planktonically or in a biofilm. Furthermore, the mutant had a truncated and asialylated lipooligosaccharide (LOS) and was substantially more serum sensitive than the wild-type. Not surprisingly, the mutant was attenuated in a mouse model for virulence, and some of the altered phenotypes were partially restored after the mutation was complemented with a functional However, no major differences were observed between the wild-type and the mutant in regard to outer membrane protein profiles, biofilm formation, EPS production, or intracellular survival. These results indicate that plays a role in virulence in the context of LOS biosynthesis but not biofilm formation or other phenotypic properties examined.
Topics: Animals; Bacterial Proteins; Biofilms; Carbon-Sulfur Lyases; Cattle; Disease Models, Animal; Genetic Variation; Genotype; Humans; Lipopolysaccharides; Mice; Pasteurellaceae; Pasteurellaceae Infections; Quorum Sensing; Sheep; Virulence
PubMed: 33139386
DOI: 10.1128/IAI.00567-20