Biochemical characterization of different genotypes of Paenibacillus larvae subsp. larvae, a honey bee bacterial pathogen

Microbiology ◽  
2004 ◽  
Vol 150 (7) ◽  
pp. 2381-2390 ◽  
Author(s):  
Sandra Neuendorf ◽  
Kati Hedtke ◽  
Gerhard Tangen ◽  
Elke Genersch
Keyword(s):  
Honey Bee ◽  
Reference Strain ◽  
Biochemical Characterization ◽  
Bacterial Pathogen ◽  
Paenibacillus Larvae ◽  
Bacterial Disease ◽  
System A ◽  
Biolog System ◽  
Far Future

Paenibacillus larvae subsp. larvae (P. l. larvae) is the aetiological agent of American foulbrood (AFB), the most virulent bacterial disease of honey bee brood worldwide. In many countries AFB is a notifiable disease since it is highly contagious, in most cases incurable and able to kill affected colonies. Genotyping of field isolates of P. l. larvae revealed at least four genotypes (AB, Ab, ab and α B) present in Germany which are genotypically different from the reference strain DSM 7030. Therefore, based on these data, five different genotypes of P. l. larvae are now identified with genotype AB standing out with a characteristic brown-orange and circled two-coloured colony morphology. Analysing the metabolic profiles of three German genotypes (AB, Ab and ab) as well as of the reference strain using the Biolog system, a characteristic biochemical fingerprint could be obtained for each strain. Cluster analysis showed that while genotypes Ab, ab and the reference strain DSM 7030 are rather similar, genotype AB is clearly different from the others. Analysis of all isolates for plasmid DNA revealed two different plasmids present only in isolates belonging to genotype AB. Therefore, genotype AB is remarkable in all aspects analysed so far. Future analysis will show whether or not these differences will expand to differences in virulence.

scholarly journals MOLECULAR AND BIOCHEMICAL CHARACTERIZATION OF STAPHYLOCOCCUS PSEUDINTERMEDIUS FROM CANINE PYODERMA IN SHIVAMOGGA REGION OF KARNATAKA

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Prashantha M K ◽  
Shambulingappa B E ◽  
Sundareshan S ◽  
Kotresh A M ◽  
Rudresh B H ◽  
...  
Keyword(s):  
Reference Strain ◽  
Biochemical Characterization ◽  
Antibiotic Resistance Gene ◽  
Meca Gene ◽  
Bacterial Pathogen ◽  
Virulence Gene ◽  
Bacterial Isolates ◽  
Isolation And Identification ◽  
Phenotypic Methods

Shivamogga. Exudate/pus/lesion swabs were collected from clinical cases of canine pyoderma (n=126) and subjected to isolation and identification of bacterial isolates by phenotypic methods. The bacteriological processing of the samples resulted in the recovery of 95 staphylococcal isolates and 18 other bacterial isolates. On culture, staphylococci were the most predominantly (n=95, 75.39%) isolated organisms. The PCR was employed as molecular method in this study for the detection of species of staphylococcal isolates by targeting nuc gene and it was also used for the detection of virulence gene and antibiotic resistance gene in staphylococcal isolates by targeting siet gene and mecA gene, respectively, by using primers published earlier. One of the S. pseudintermedius isolates which confirmed by PCR and sequencing of partial nuc gene was used as positive reference strain for further screening of isolates by PCR. Based on nuc gene-based PCR, out of 95 staphylococcal isolates obtained, 82 (86.1%)of the isolates were found belonging to S. pseudintermedius. And out of 82 S. pseudintermedius isolates, siet gene was detected in 69 (86.1%) isolates. S. pseudintermedius was found to be predominant bacterial pathogen responsible for pyoderma in dogs.

scholarly journals Characterization of CRISPR Spacer and Protospacer Sequences in Paenibacillus larvae and Its Bacteriophages

Viruses ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 459
Author(s):  
Casey Stamereilers ◽  
Simon Wong ◽  
Philippos K. Tsourkas
Keyword(s):  
Comparative Studies ◽  
Point Mutations ◽  
Paenibacillus Larvae ◽  
Bacterial Disease ◽  
American Foulbrood ◽  
Antibiotic Resistant ◽  
Future Studies ◽  
Complete Genomes ◽  
Point Of Reference

The bacterium Paenibacillus larvae is the causative agent of American foulbrood, the most devastating bacterial disease of honeybees. Because P. larvae is antibiotic resistant, phages that infect it are currently used as alternative treatments. However, the acquisition by P. larvae of CRISPR spacer sequences from the phages could be an obstacle to treatment efforts. We searched nine complete genomes of P. larvae strains and identified 714 CRISPR spacer sequences, of which 384 are unique. Of the four epidemiologically important P. larvae strains, three of these have fewer than 20 spacers, while one strain has over 150 spacers. Of the 384 unique spacers, 18 are found as protospacers in the genomes of 49 currently sequenced P. larvae phages. One P. larvae strain does not have any protospacers found in phages, while another has eight. Protospacer distribution in the phages is uneven, with two phages having up to four protospacers, while a third of phages have none. Some phages lack protospacers found in closely related phages due to point mutations, indicating a possible escape mechanism. This study serve a point of reference for future studies on the CRISPR-Cas system in P. larvae as well as for comparative studies of other phage–host systems.

scholarly journals Characterization of natural populations of Drosophila melanogaster with regard to the hobo system: a new hypothesis on the invasion

1997 ◽  
Vol 69 (3) ◽  
pp. 197-208 ◽  
Author(s):  
ERIC BONNIVARD ◽  
DOMINIQUE HIGUET ◽  
CLAUDE BAZIN
Keyword(s):  
Drosophila Melanogaster ◽  
Reference Strain ◽  
Natural Populations ◽  
Hybrid Dysgenesis ◽  
Molecular Characteristics ◽  
Male Recombination ◽  
System A ◽  
Genetic Level ◽  
New Hypothesis

Until now, with regard to the hobo system of hybrid dysgenesis, natural populations of Drosophila melanogaster have been investigated using only two criteria: at the molecular level, the presence or absence of XhoI fragments 2·6 kb long or smaller; and/or at the genetic level, the ability to induce gonadal dysgenesis sterility in crosses A (females of an E reference strain crossed with males under test) and A* (females under test crossed with males of an H reference strain). Recently, analyses of laboratory strains using these criteria as well as the mobilization of two reporter genes, the male recombination and the number of ‘TPE’ repeats in the S region, revealed a lack of correlation between the different dysgenic parameters themselves, and also between these parameters and the molecular characteristics of the strains. Thirteen current strains derived from world populations were therefore investigated with regard to all these dysgenic traits, to determine discriminating criteria providing a robust method of classifying natural populations and deducing the dynamics of hobo elements in these populations. We show, as in laboratory strains, a lack of correlation between the parameters studied. Therefore, the significance of each of them as well as the nature of hobo hybrid dysgenesis are discussed, to propose an analysis method of the hobo system applicable to natural populations. According to the geographical distribution of hobo activities in world populations and to the variable polymorphism of the number of ‘TPE’ repeats, we propose a new scenario for the invasion of D. melanogaster by hobo elements.

scholarly journals Genetic and Biochemical Characterization of CGB-1, an Ambler Class B Carbapenem-Hydrolyzing β-Lactamase from Chryseobacterium gleum

2002 ◽  
Vol 46 (9) ◽  
pp. 2791-2796 ◽  
Author(s):  
Samuel Bellais ◽  
Thierry Naas ◽  
Patrice Nordmann
Keyword(s):  
Reference Strain ◽  
Biochemical Characterization ◽  
Amino Acid Identity ◽  
Relative Molecular Mass ◽  
Class A ◽  
Molecular Subclass ◽  
Class B ◽  
Lactamase Gene ◽  
Chryseobacterium Gleum

ABSTRACT Chryseobacterium gleum (previously included in the Flavobacterium IIb species) is a gram-negative aerobe that is a source of nosocomial infections. An Ambler class B β-lactamase gene was cloned and expressed in Escherichia coli from reference strain C. gleum CIP 103039 that had reduced susceptibility to expanded-spectrum cephalosporins and carbapenems. The purified β-lactamase, CGB-1, with a pI value of 8.6 and a determined relative molecular mass of ca. 26 kDa, hydrolyzed penicillins; narrow- and expanded-spectrum cephalosporins; and carbapenems. CGB-1 was a novel member of the molecular subclass B1 of metallo-enzymes. It had 83 and 42% amino acid identity with IND-1 from Chryseobacterium indologenes and BlaB from C. meningosepticum, respectively. Thus, in addition to the previously characterized clavulanic acid-inhibited extended-spectrum β-lactamase CGA-1 of Ambler class A, C. gleum produces a very likely chromosome-borne class B β-lactamase.

scholarly journals Biochemical characterization of Bacillus thuringiensis cytolytic toxins in association with a phospholipid bilayer

1999 ◽  
Vol 338 (1) ◽  
pp. 185-193 ◽  
Author(s):  
Jinping DU ◽  
Barbara H. KNOWLES ◽  
Jade LI ◽  
David J. ELLAR
Keyword(s):  
Biochemical Characterization ◽  
Bound State ◽  
Phospholipid Bilayer ◽  
Membrane Pore ◽  
Glucose Release ◽  
System A ◽  
Molecular Masses ◽  
Release Assay ◽  
Membrane Bound

The interaction of two Bacillus thuringiensiscytolytic toxins, CytA and CytB, with a phospholipid bilayer and their structure in the membrane-bound state were investigated by proteolysis using phospholipid vesicles as a model system. A toxin conformational change upon membrane binding was detected by comparing the proteolytic profile of membrane-bound toxin and saline-solubilized toxin. When membrane-bound toxin was exposed to protease K or trypsin, novel cleavage sites were found between the α-helical N-terminal half and β-strand C-terminal half of the structure at K154 and N155 in CytA and at I150 and G141 in CytB. N-terminal sequencing of membrane-protected fragments showed that the C-terminal half of the toxin structure comprising mainly β-strands was inserted into the membrane, whereas the N-terminal half comprising mainly α-helices was exposed on the outside of the liposomes and could be removed when liposomes with bound toxin were washed extensively after proteolysis. The C-termini of the membrane-inserted proteolytic fragments were also located by a combination of N-terminal sequencing and measurement of the molecular masses of the fragments by electrospray MS. Using a liposome glucose-release assay, the membrane-inserted structure was seen to retain its function as a membrane pore even after removal of exposed N-terminal segments by proteolysis. These data strongly suggest that the pores for glucose release are assembled from the three major β-strands (β-5, β-6 and β-7) in the C-terminal half of the toxin.

scholarly journals Isolation and Characterization of Brenneria quercina, Causal Agent for Bark Canker and Drippy Nut of Quercus spp. in Spain

2003 ◽  
Vol 93 (4) ◽  
pp. 485-492 ◽  
Author(s):  
Elena G. Biosca ◽  
Raquel González ◽  
María José López-López ◽  
Santiago Soria ◽  
Carmina Montón ◽  
...  
Keyword(s):  
Fungal Pathogens ◽  
Reference Strain ◽  
Biochemical Characterization ◽  
Causal Agent ◽  
Enzyme Linked Immunosorbent Assay ◽  
Isolation And Characterization ◽  
Pathogenicity Tests ◽  
Different Origins ◽  
First Time

The drippy nut disease of oak was first described in California in 1967 and, since then, the causal agent has not been reported in any other area. This study describes for the first time in Europe the isolation of Brenneria (Erwinia) quercina from bark canker in addition to drippy bud and drippy nut in Quercus ilex and Q. pyrenaica. The bark canker and drippy bud symptoms were not previously described as caused by this bacterium. No fungal pathogens were associated with any of the symptoms. Physiological and biochemical characterization identified the pathogenic isolates from Spain as belonging to B. quercina, similar to the reference strain CFBP 1266. Fatty acid profiles of the Spanish isolates also were similar to the strain of B. quercina from California. Serological analysis by indirect immunofluorescence and enzyme-linked immunosorbent assay using polyclonal antisera against the reference strain of B. quercina and one Spanish oak isolate revealed some antigenic heterogeneity between isolates of different origins. Pathogenicity tests demonstrated that the Spanish isolates were able to reproduce internal symptoms of necrosis and acorn exudation in Q. ilex and Q. pyrenaica and suggest that B. quercina may be associated, among other causes, with the oak decline syndrome affecting Spanish oak forests.

scholarly journals American foulbrood and its causative agent, Paenibacillus larvae, in New Zealand’s registered hives and apiaries

2021 ◽  
Author(s):  
◽  
Samantha Amy Montrose Graham
Keyword(s):  
New Zealand ◽  
Statistical Analysis ◽  
Genetic Analysis ◽  
Honey Bee ◽  
Causative Agent ◽  
Management Strategies ◽  
Paenibacillus Larvae ◽  
Bacterial Disease ◽  
American Foulbrood ◽  
Infection Rates

<p>Though the honey bee (Apis mellifera) is exposed to an extensive diversity of parasites and pathogens from multiple kingdoms, few are as devastating as American foulbrood. American foulbrood is a highly contagious bacterial disease, of which the causative agent (bacterium Paenibacillus larvae) infects honey bee brood through the ingestion of its spores, ultimately leading to the death of the infected larva and the collapse of the infected hive. Paenibacillus larvae’s genotypes (ERIC I-IV) exhibit differing ‘killing time’ of infected larvae, resulting in different larval and colony level virulence of the disease within hives.  American foulbrood is found in New Zealand’s registered hives, and poses a threat to the country’s apiculture industry. The first objective of this thesis was to perform a genetic analysis on New Zealand’s P. larvae field strains using the well-established methodology of rep-PCR with MBO REP1 primers. A total of 172 bacteria isolates were gathered from registered hives from 2011 to 2014 and examined. The MBO REP1 primer identifies the ‘beta’ genetic subgroups of P. larvae. By identifying beta subgroups, the ERIC genotypes that are present in New Zealand can also be concluded. The genetic analysis of P. larvae using rep-PCR is a first for New Zealand, and appears to be a first for Australasia. The second objective of this thesis was to conduct a temporal and geographical statistical analysis on American foulbrood infection rate trends in New Zealand’s national and regional, divided into seven regions, registered hives and apiaries from 1994 to 2013.  The genetic analysis of P. larvae detected three ‘beta’ genotypic subgroups: B, b, and Б. From these findings it was concluded that ERIC I and ERIC II are present in New Zealand. Previous to my findings, subgroup B and Б and ERIC II genotype had not been recorded outside of Europe. The statistical analysis reported that American foulbrood infection rates were significantly decreasing nationally. Results also reported that four of the seven regions’ infection rates were significantly decreasing, whilst three regions were significantly increasing.  Conclusions on the subgroups and genotypes present in New Zealand gives the first insight to the virulence and occurrence of P. larvae strains. Additionally, the use of rep-PCR for the genetic analysis of P. larvae enables this thesis to contribute to the increasing knowledge on American foulbrood. By examining the temporal and geographic dynamics of American foulbrood, the results allow for the evaluation of current management strategies and the most recent understanding on the national and regional infection rates of the disease.</p>

scholarly journals American foulbrood and its causative agent, Paenibacillus larvae, in New Zealand’s registered hives and apiaries

2021 ◽  
Author(s):  
◽  
Samantha Amy Montrose Graham
Keyword(s):  
New Zealand ◽  
Statistical Analysis ◽  
Genetic Analysis ◽  
Honey Bee ◽  
Causative Agent ◽  
Management Strategies ◽  
Paenibacillus Larvae ◽  
Bacterial Disease ◽  
American Foulbrood ◽  
Infection Rates

<p>Though the honey bee (Apis mellifera) is exposed to an extensive diversity of parasites and pathogens from multiple kingdoms, few are as devastating as American foulbrood. American foulbrood is a highly contagious bacterial disease, of which the causative agent (bacterium Paenibacillus larvae) infects honey bee brood through the ingestion of its spores, ultimately leading to the death of the infected larva and the collapse of the infected hive. Paenibacillus larvae’s genotypes (ERIC I-IV) exhibit differing ‘killing time’ of infected larvae, resulting in different larval and colony level virulence of the disease within hives.  American foulbrood is found in New Zealand’s registered hives, and poses a threat to the country’s apiculture industry. The first objective of this thesis was to perform a genetic analysis on New Zealand’s P. larvae field strains using the well-established methodology of rep-PCR with MBO REP1 primers. A total of 172 bacteria isolates were gathered from registered hives from 2011 to 2014 and examined. The MBO REP1 primer identifies the ‘beta’ genetic subgroups of P. larvae. By identifying beta subgroups, the ERIC genotypes that are present in New Zealand can also be concluded. The genetic analysis of P. larvae using rep-PCR is a first for New Zealand, and appears to be a first for Australasia. The second objective of this thesis was to conduct a temporal and geographical statistical analysis on American foulbrood infection rate trends in New Zealand’s national and regional, divided into seven regions, registered hives and apiaries from 1994 to 2013.  The genetic analysis of P. larvae detected three ‘beta’ genotypic subgroups: B, b, and Б. From these findings it was concluded that ERIC I and ERIC II are present in New Zealand. Previous to my findings, subgroup B and Б and ERIC II genotype had not been recorded outside of Europe. The statistical analysis reported that American foulbrood infection rates were significantly decreasing nationally. Results also reported that four of the seven regions’ infection rates were significantly decreasing, whilst three regions were significantly increasing.  Conclusions on the subgroups and genotypes present in New Zealand gives the first insight to the virulence and occurrence of P. larvae strains. Additionally, the use of rep-PCR for the genetic analysis of P. larvae enables this thesis to contribute to the increasing knowledge on American foulbrood. By examining the temporal and geographic dynamics of American foulbrood, the results allow for the evaluation of current management strategies and the most recent understanding on the national and regional infection rates of the disease.</p>

Sign in / Sign up

Export Citation Format

Share Document