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Vaccines Mar 2024are a group of Gram-negative bacteria that can cause a variety of diseases in at-risk populations. and , the etiological agents of melioidosis and glanders,... (Review)
Review
are a group of Gram-negative bacteria that can cause a variety of diseases in at-risk populations. and , the etiological agents of melioidosis and glanders, respectively, are the two clinically relevant members of the complex (Bpc). The development of vaccines against Bpc species has been accelerated in recent years, resulting in numerous promising subunits and glycoconjugate vaccines incorporating a variety of antigens. However, a second group of pathogenic species exists known as the complex (Bcc), a group of opportunistic bacteria which tend to affect individuals with weakened immunity or cystic fibrosis. To date, there have been few attempts to develop vaccines to Bcc species. Therefore, the primary goal of this review is to provide a broad overview of the various subunit antigens that have been tested in Bpc species, their protective efficacy, study limitations, and known or suspected mechanisms of protection. Then, we assess the reviewed Bpc antigens for their amino acid sequence conservation to homologous proteins found in Bcc species. We propose that protective Bpc antigens with a high degree of Bpc-to-Bcc sequence conservation could serve as components of a pan- vaccine capable of protecting against both disease-causing groups.
PubMed: 38543947
DOI: 10.3390/vaccines12030313 -
Archives of Razi Institute Aug 2023is the main cause of glanders as a dangerous contagious zoonosis disease that is mostly observed in single-hoofed animals, especially horses. Modern molecular...
is the main cause of glanders as a dangerous contagious zoonosis disease that is mostly observed in single-hoofed animals, especially horses. Modern molecular techniques have been recently employed to improve epidemiology for identifying and searching for strains of this bacterium at different times and locations. Due to the unknown number of circulating strains and lack of preventive methods, glanders is still observed in the form of epidemics. The present study aimed to evaluate six field isolates plus two laboratory strains of and using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. All the isolates and strains were microbially cultured in the glycerol nutrient and glycerol agar media. The individually grown colonies of the bacterium were used in the biochemical tests. The DNA of isolates was extracted by boiling, and the PCR-RFLP test was conducted on their genome. Finally, the bacterium was injected into guinea pigs to induce the Straus reaction. The biochemical assays (or bioassays) confirmed the isolates as . The PCR-RFLP assay demonstrated a product for with a length of 650 bp. Nevertheless, 250 and 400 bp were produced for . The swollen scrotum pointed to the occurrence of the Straus reaction. The PCR-RFLP is a proper differential diagnosis technique for ; moreover, it is a suitable method for differentiating between and . This technique can detect in a short time with high precision and sensitivity.
Topics: Horses; Animals; Guinea Pigs; Burkholderia mallei; Glanders; Polymorphism, Restriction Fragment Length; Glycerol; Burkholderia pseudomallei; Polymerase Chain Reaction; Horse Diseases
PubMed: 38226390
DOI: 10.32592/ARI.2023.78.4.1305 -
Brazilian Journal of Microbiology :... Jun 2023Glanders is a contagious disease of equids caused by the Gram-negative bacterium Burkholderia mallei. In Brazil, the disease is considered to be reemerging and has been...
Glanders is a contagious disease of equids caused by the Gram-negative bacterium Burkholderia mallei. In Brazil, the disease is considered to be reemerging and has been expanding, with records of equids with positive serology in most of the federative units. However, there are few reports describing the genotypic detection of the agent. This study demonstrated the detection of B. mallei by species-specific PCR directly from tissues or from bacterial cultures, followed by amplicon sequencing in equids (equines, mules, and asinines) with positive serology for glanders in all five geographic regions of Brazil. The molecular evidence of B. mallei infection in serologically positive equids in this study expands the possibility of strain isolation and the conduction of epidemiological characterizations based on molecular information. The microbiological detection of B. mallei in cultures from nasal and palate swabs, even in equids without clinical manifestations, raises the possibility of environmental elimination of the agent.
Topics: Animals; Horses; Burkholderia mallei; Glanders; Brazil; Polymerase Chain Reaction; Nucleic Acid Amplification Techniques
PubMed: 37074557
DOI: 10.1007/s42770-023-00965-9 -
Frontiers in Veterinary Science 2024Glanders is a highly infectious and notifiable disease of equines that occurs due to . In India, glanders re-emerged in 2006 and thereafter regular outbreaks have been...
Glanders is a highly infectious and notifiable disease of equines that occurs due to . In India, glanders re-emerged in 2006 and thereafter regular outbreaks have been reported in various states ( = 14). Frequent and prolonged contact with equids with glanders may transmit infection to humans. This study was designed to learn more about the Knowledge, Awareness and Perception (KAP) of veterinarians, para veterinarians, and physicians about equine glanders, which will help in enhancing the nation-wide glanders eradication programme. A total of 165 respondent's from 11 Indian states and one union territory were surveyed. Most of the respondents ( = 160) were from equine glanders affected or endemic states. Knowledge gap analysis revealed that 40.3 and 22% of the participants were not aware of government regulations and the transmission of glanders, respectively. These are major concerns given the wide spread occurrence of disease in the country. Awareness test on glanders revealed that 65(39.4%) participants would collect biological samples for laboratory confirmation, 67(40.6%) would inform the concerned authorities and 106 (64.2%) replied that they would eliminate the glanders infected equines. Analysis of perception towards equine glanders showed that majority of the participants ( = 113, 68.4%) observed that equine keepers were reluctant to disclose the clinical symptoms of infection. Furthermore, non-co-operation and unwillingness by superiors (33.9%), financial (31%), administrative (28.4%), and technical limitations (27.8%) were major constraints under the perception analysis. This study reveals that veterinarians need to be educated on governmental policies and guidelines on equine glanders with regular training and awareness programs. Intersectoral co-ordination to investigate human glanders is also needed.
PubMed: 38550783
DOI: 10.3389/fvets.2024.1334485 -
Frontiers in Veterinary Science 2023Glanders is a highly contagious and life-threatening zoonotic disease caused by (). Without an effective vaccine or treatment, early diagnosis has been regarded as the...
Glanders is a highly contagious and life-threatening zoonotic disease caused by (). Without an effective vaccine or treatment, early diagnosis has been regarded as the most effective method to prevent glanders transmission. Currently, the diagnosis of glanders is heavily reliant on serological tests. However, given that markedly different host immune responses can be elicited by genetically different strains of the same bacterial species, infection by , whose genome is unstable and plastic, may result in various immune responses. This variability can make the serodiagnosis of glanders challenging. Therefore, there is a need for a comprehensive understanding and assessment of how genomic variations impact the appropriateness of specific target antigens for glanders serodiagnosis. In this study, we investigated how genomic variations in the genome affect gene content (gene presence/absence) and expression, with a special focus on antigens used or potentially used in serodiagnosis. In all the genome sequences of isolates available in NCBI's RefSeq database (accessed in July 2023) and in-house sequenced samples, extensive small and large variations were observed when compared to the type strain ATCC 23344. Further pan-genome analysis of those assemblies revealed variations of gene content among all available genomes of . Specifically, differences in gene content ranging from 31 to 715 genes with an average of 334 gene presence-absence variations were found in strains with complete or chromosome-level genome assemblies, using the ATCC 23344 strain as a reference. The affected genes included some encoded proteins used as serodiagnostic antigens, which were lost due mainly to structural variations. Additionally, a transcriptomic analysis was performed using the type strain ATCC 23344 and strain Zagreb which has been widely utilized to produce glanders antigens. In total, 388 significant differentially expressed genes were identified between these two strains, including genes related to bacterial pathogenesis and virulence, some of which were associated with genomic variations, particularly structural variations. To our knowledge, this is the first comprehensive study to uncover the impacts of genetic variations of on its gene content and expression. These differences would have significant impacts on host innate and adaptive immunity, including antibody production, during infection. This study provides novel insights into genetic variants, knowledge which will help to improve glanders serodiagnosis.
PubMed: 38125681
DOI: 10.3389/fvets.2023.1217135 -
BMC Research Notes Mar 2024In this study, we sought to determine the types and prevalence of antimicrobial resistance determinants (ARDs) in Burkholderia spp. strains using the Antimicrobial...
OBJECTIVE
In this study, we sought to determine the types and prevalence of antimicrobial resistance determinants (ARDs) in Burkholderia spp. strains using the Antimicrobial Resistance Determinant Microarray (ARDM).
RESULTS
Whole genome amplicons from 22 B. mallei (BM) and 37 B. pseudomallei (BP) isolates were tested for > 500 ARDs using ARDM v.3.1. ARDM detected the following Burkholderia spp.-derived genes, aac(6), bla, blaA, penA-BP, and qacE, in both BM and BP while bla, macB, bla and penA-BC were observed in BP only. The method of denaturing template for whole genome amplification greatly affected the numbers and types of genes detected by the ARDM. Bla was detected in nearly a third of BM and BP amplicons derived from thermally, but not chemically denatured templates. Bla results were confirmed by PCR, with 81% concordance between methods. Sequences from 414-nt PCR amplicons (13 preparations) were 100% identical to the Klebsiella pneumoniae reference gene. Although bla sequences have been observed in B. glumae, B. cepacia, and other undefined Burkholderia strains, this is the first report of such sequences in BM/BP/B. thailandensis (BT) clade. These results highlight the importance of sample preparation in achieving adequate genome coverage in methods requiring untargeted amplification before analysis.
Topics: Humans; Burkholderia mallei; Burkholderia pseudomallei; Burkholderia; Anti-Infective Agents; Respiratory Distress Syndrome
PubMed: 38475810
DOI: 10.1186/s13104-024-06717-8 -
Life Science Alliance Feb 2024Intracellular bacteria are threatened by ubiquitin-mediated autophagy, whenever the bacterial surface or enclosing membrane structures become targets of host ubiquitin...
Intracellular bacteria are threatened by ubiquitin-mediated autophagy, whenever the bacterial surface or enclosing membrane structures become targets of host ubiquitin ligases. As a countermeasure, many intracellular pathogens encode deubiquitinase (DUB) effectors to keep their surfaces free of ubiquitin. Most bacterial DUBs belong to the OTU or CE-clan families. The betaproteobacteria and , causative agents of melioidosis and glanders, respectively, encode the TssM effector, the only known bacterial DUB belonging to the USP class. TssM is much shorter than typical eukaryotic USP enzymes and lacks the canonical ubiquitin-recognition region. By solving the crystal structures of isolated TssM and its complex with ubiquitin, we found that TssM lacks the entire "Fingers" subdomain of the USP fold. Instead, the TssM family has evolved the functionally analog "Littlefinger" loop, which is located towards the end of the USP domain and recognizes different ubiquitin interfaces than those used by USPs. The structures revealed the presence of an N-terminal immunoglobulin-fold domain, which is able to form a strand-exchange dimer and might mediate TssM localization to the bacterial surface.
Topics: Humans; Horses; Animals; Burkholderia pseudomallei; Burkholderia mallei; Glanders; Melioidosis; Ubiquitin
PubMed: 38170641
DOI: 10.26508/lsa.202302422 -
Microorganisms Oct 2023is an aerobic, Gram-negative, non-motile bacillus. As an obligate mammalian pathogen, it primarily affects solipeds. Although rarely transmitted to humans, the disease...
is an aerobic, Gram-negative, non-motile bacillus. As an obligate mammalian pathogen, it primarily affects solipeds. Although rarely transmitted to humans, the disease it causes, glanders, is classified as a zoonosis. The bacterium was officially eradicated in Brazil in 1969; however, it reemerged after three decades. This study aims to assess the virulence of a specific strain, isolated in Brazil, in BALB/c mice through intranasal infection. The strain, BAC 86/19, was obtained from the tracheal secretion of a young mare displaying positive serology but no clinical signs of glanders. Post-mortem examinations revealed macroscopic lesions consistent with the disease, however. In mice, the LD was determined to be approximately 1.59 × 10 colony-forming units (CFU)/animal. Mice exposed to either 0.1 × LD or 1 × LD displayed transient weight loss, which resolved after three or five days, respectively. persisted within the liver and lung for five days post-infection and in the spleen for seven days. These findings underscore the detectable virulence of the Brazilian BAC 86/19 strain in mice, which are relatively resilient hosts. This research points to the importance of the continued investigation of the virulence mechanisms and potential countermeasures associated with infections, including their Brazilian isolates.
PubMed: 37894255
DOI: 10.3390/microorganisms11102597 -
Pathogens (Basel, Switzerland) Oct 2023This manuscript elucidates the occurrence of glanders in an asymptomatic mare from Brazil presenting positive antibody titers. The diagnosis was established through a...
This manuscript elucidates the occurrence of glanders in an asymptomatic mare from Brazil presenting positive antibody titers. The diagnosis was established through a multi-pronged approach encompassing microbiological culture, mass spectrometry, and genome sequencing. The outbreak occurred in 2019 in Tatuí, São Paulo, Brazil, and the infected mare, despite displaying no clinical symptoms, had multiple miliary lesions in the liver, as well as intense catarrhal discharge in the trachea. Samples were collected from various organs and subjected to bacterial isolation, molecular detection, and identification. The strain was identified as using PCR and confirmed by MALDI-TOF mass spectrometry. Whole-genome sequencing revealed a genome size of 5.51 Mb with a GC content of 65.8%, 5871 genes (including 4 rRNA and 53 tRNA genes), and 5583 coding DNA sequences (CDSs). Additionally, 227 predicted pseudogenes were detected. In silico analysis of different genomic loci that allow for differentiation with confirmed the identity of the isolate as , in addition to the characteristic genome size. The BAC 86/19 strain was identified as lineage 3, sublineage 2, which includes other strains from Brazil, India, and Iran. The genome sequencing of this strain provides valuable information that can be used to better understand the pathogen and its epidemiology, as well as to develop diagnostic tools for glanders.
PubMed: 37887766
DOI: 10.3390/pathogens12101250