Genome-Wide SNP-genotyping array to study the evolution of the human pathogen Vibrio vulnificus Biotype 3

Vibrio vulnificus is an aquatic bacterium and an important human pathogen. Strains Of V. vulnificus are classified into three different biotypes. The newly emerged biotype 3 has been found to be clonal and restricted to Israel. In the family Vibrionaceae , horizontal gene transfer is the main mechanism responsible for the emergence of new pathogen groups. To better understand the evolution of the bacterium, and in particular to trace the evolution of biotype 3, we performed genome-wide SNP genotyping of 254 clinical and environmental V. vulnificus isolates with worldwide distribution recovered over a 30-year period, representing all phylogeny groups. A custom single-nucleotide polymorphism (SNP) array implemented on the Illumina GoldenGate platform was developed based on 570 SNPs randomly distributed throughout the genome. In general, the genotyping results divided the V. vulnificus species into three main phylogenetic lineages and an additional subgroup, clade B, consisting of environmental and clinical isolates from Israel. Data analysis suggested that 69% of biotype 3 SNPs are similar to SNPs from clade B, indicating that biotype 3 and clade B have a common ancestor. The rest of the biotype 3 SNPs were scattered along the biotype 3 genome, probably representing multiple chromosomal segments that may have been horizontally inserted into the clade B recipient core genome from other phylogroups or bacterial species sharing the same ecological niche. Results emphasize the continuous evolution of V. vulnificus and support the emergence of new pathogenic groups within this species as a recurrent phenomenon. Our findings contribute to a broader understanding of the evolution of this human pathogen

Comparison of the biotypes of Yersinia enterocolitica isolated from pigs, cattle and sheep at slaughter and from humans with yersiniosis in Great Britain during 1999-2000

Aims: To investigate the relationship between livestock carriage of Yersinia enterocolitica and human disease. The biotypes/serotypes of strains recovered from the faeces of pigs, cattle and sheep at slaughter during a national survey in Great Britain in 1999-2000, were compared with those of strains isolated from human cases of yersiniosis during the same period. Methods and Results: The faecal carriage of Y. enterocolitica by cattle, sheep and pigs at slaughter was 6.3, 10.7 and 26.1%, respectively. Yersinia enterocolitica biotype (BT) 1a was the most frequently isolated biotype from livestock (58%) and was the predominant biotype (53%) isolated from human cases over the same period. The main recognized pathogenic Y. enterocolitica biotype isolated from livestock was BT3 (O:5,27) (35% of sheep, 22% of pigs and 4% of cattle) but this biotype was not detected in any of the human isolates investigated. The major pathogenic biotypes of strains isolated from humans were BT3 (O:9) (24%) and BT4 (O:3) (19%) whereas of the veterinary isolates investigated, only pigs (11%) carried BT3 (O:9) strains. Conclusions: Because of significant overlaps in phenotypes of the veterinary and human strains it is not possible to comment on the correlation between host and pathogenicity, especially of biotype 1a. Significance and Impact of the Study: The data suggest that further investigations using methods with greater discriminatory power are required. However the data also suggests that pigs may be the primary reservoir for human pathogenic Y. enterocolitica infection

Clinical Characteristics and Molecular Subtyping of Vibrio vulnificus Illnesses, Israel

The genetically distinct biotype 3 has penetrated Israeli freshwaters and is causing severe illness in persons who handle tilapia or carp

Uji Ketahanan Galur Padi Terhadap Wereng Coklat Biotipe 3 Melalui Population Build-up

Screening of rice lines resistance to brown planthopper (BPH) through mass screening, filtering line resistance and the population build-up are essential for the release of resistant rice varieties. In addition, the stages of the endurance are important in determining the stability of resistance, as well as the type of resistant. The research was carried out in the screen house at Indonesian Center for Rice Research in 2007. The BPH used in the research was the off spring of BPH biotype 3 that had been rearing on IR42 (bph2) variety since 1994. The result of this research showed that 22.2% of 18 lines/varieties were moderately resistant to BPH biotype 3ft namely BP4130-1f-13-3-2*B, BP4188-7f-1-2-2*B, BP2870-4e- Kn-22-2-1-5*B, and Pulut Lewok. On the population build-up test, the above lines/varieties were moderately resistant to BPH biotype 3pb. The low FPLI values were found in BP4130-1f-13-3-2*B and Pulut Lewok. The highest tolerance index was found on BP4130-1f- 13-3-2*B and Pulut Lewok followed by BP2870-4e-Kn-22-2-1-5*B and BP4188-7f-1-2-2*B. Pulut Lewok has the highest antibiosis index and is not significantly different to BP4130-1f-13-3-2*B, while BP4188-7f-1-2-2*B was lowest. Although Pulut Lewok has antibiosis defense mechanism, it is not tolerant to BPH biotype 3. The BP4130-1f-13-3-2*B line have both antibiosis and tolerant to BPH biotype 3. BP4188-7f-1-2-2*B line has tolerance character, but does not have character of antibiosis to BPH biotype 3

Effect of Host Plant on the Level of Virulence of \u3ci\u3eNilaparvata lugens\u3c/i\u3e (Homoptera: Delphacidae) on Rice Cultivars

The virulence of a planthopper, Nilaparvata lugens (Stål) biotype 3, reared on rice cultivar ASD7and of N. lugens colonies collected on Mindanao Island in the southern Philippines and reared on the widely grown commercial cultivars IR36 and IR42 was compared. Based on plant damage, insect weight, population growth, and feeding activity, the Mindanao N. lugens colonies reared on IR36 and IR42 were more virulent than biotype 3, although ASD7, IR36, and IR42 have the bph2 gene for N. lugens resistance. These results clearly indicate that in the screening of breeding lines for resistance to N. lugens, it is important to use insect populations reared on cultivars similar to those grown in farmers’ fields. Failure to do so may result in the release of a cultivar that is susceptible to the N. lugens field population

APPLICATION OF MALDI-TOF MASS SPECTROMETRY AS A TOOL FOR BIOTYPING OF B. MELITENSIS

Background: Brucellosis is a global zoonosis caused by the bacteria of the genus Brucella a hazard group III pathogen. Typing of Brucella species is of great importance for understanding the epidemiology of the disease and an essential tool for the eradication program and vaccine development. The aim of the present study is to evaluate Matrix-assisted laser desorption ion-ization- time of flight spectrometry (MALDI-TOF MS), a proteomic based as-say, for biotyping B. melitensis in Qatar. Methodology: A total of sixty three B. melitensis isolated from clinical spec-imens, were biochemically identified by Vitek 2 Compact and serotyped us-ing monospecific Brucella antisera. MALDI-TOF MS Identification was car-ried out against the newly constructed Brucella library. Subsequently, MALDI typing was performed by visual inspection of the generated spectra to determine potential biotype-specific marker peaks. Molecular typing was performed using B. melitensis biotyping PCR kit as a reference method. Results: MALDI-TOF MS identified all the isolates as B. melitensis with a score of >2.3 indicating highly probable species identification. The visual in-spection of the generated spectra revealed six promising marker peaks at m/z 4682, 5028, 5970, 6823, 7356, and 7326. The presence or absence of these marker peaks grouped the isolates into four groups with four distinct marker peak profiles. PCR typing results showed the presence of only two biotypes, B. melitensis biotype 2 (n=32) and B. melitensis biotype 3 (n=31). The mass spectral profiles that share the marker peak at m/z 7356 (n=32) were confirmed as biotype 2 while the mass spectral profiles that share the marker peak at m/z 5970 (n=31) as biotype 3. No B. melitensis biotype 1 was detected in this study. Conclusion: Human brucellosis in Qatar is exclusively caused by B. melitensis with equal distribution of biotype 2 and biotype 3. MALDI-TOF MS was found to be a promising tool to identify and differentiate B. melitensis biotypes 2 and 3. Peak at m/z 7356 was identified as biotype 2-specific marker peak and peak at m/z 5970 as biotype 3-specific.Hamad Medical Corporatio

Epidemiologic Study of Vibrio vulnificus Infections by Using Variable Number Tandem Repeats

A 3-year environmental and clinical Vibrio vulnificus survey using simple-sequence repeats typing shows that V. vulnificus biotype 3 constitutes ≈21% of the bacterium population in tested aquaculture ponds as opposed to ≈86% of clinical cases. Simple-sequence repeats proved to be a useful epidemiologic tool, providing information on the environmental source of the pathogen

Reduced Fitness of Virulent Aphis glycines (Hemiptera: Aphididae) Biotypes May Influence the Longevity of Resistance Genes in Soybean

Sustainable use of insect resistance in crops require insect resistance management plans that may include a refuge to limit the spread of virulence to this resistance. However, without a loss of fitness associated with virulence, a refuge may not prevent virulence from becoming fixed within a population of parthenogenetically reproducing insects like aphids. Aphid-resistance in soybeans (i.e., Rag genes) prevent outbreaks of soybean aphid (Aphis glycines), yet four biotypes defined by their capacity to survive on aphid-resistant soybeans (e.g., biotype-2 survives on Rag1 soybean) are found in North America. Although fitness costs are reported for biotype-3 on aphid susceptible and Rag1 soybean, it is not clear if virulence to aphid resistance in general is associated with a decrease in fitness on aphid susceptible soybeans. In laboratory assays, we measured fitness costs for biotype 2, 3 and 4 on an aphid-susceptible soybean cultivar. In addition, we also observed negative cross-resistance for biotype-2 onRag3, and biotype-3 on Rag1 soybean. We utilized a simple deterministic, single-locus, four compartment genetic model to account for the impact of these findings on the frequency of virulence alleles. When a refuge of aphid susceptible was included within this model, fitness costs and negative cross-resistance delayed the increase of virulence alleles when virulence was inherited recessively or additively. If virulence were inherited additively, fitness costs decreased the frequency of virulence. Combined, these results suggest that a refuge may prevent virulent A. glycines biotypes from overcoming Rag genes if this aphid-resistance were used commercially in North America

Virulence of Brown Planthopper and Development of Core Collection of the Pest

Brown planthopper is the most important rice pest in Indonesia. Its high adaptability to feed and reproduce on previously introduced resistant varieties to form more virulent population often causes BPH outbreak and hopperburn that lead to total crop yield loss. Rice breeding for resistant to BPH requires information on the current status of BPH virulences in the fields to anticipate the virulence adaptation on new varieties. The objectives of this study were to investigate the degree of virulence of BPH populations and to cluster the BPH virulence to form BPH core collection. Thirteen BPH populations collected from paddy fields in six provinces (Banten, West Java, Central Java, East Java, South Kalimantan, and South Sulawesi) in 2011 and 2013 were tested on 10 differential rice varieties and seven host varieties of BPH populations, using the standard seedbox screening technique. Based on resistance reaction of four differential varieties (TN1, Mudgo, ASD7, and Rathu Heenathi), most BPH populations were identified as more virulent than biotype 4 (T1, Banten, PG, West Java; BY, East Java; B2 and B3, South Kalimantan; X1 and X3, South Sulawesi), four populations were biotype 4 (JWDL, Central Java; SD, East Java; X2 and X4, South Sulawesi), and one population each was biotype 3 (T2, Banten) and biotype 2 (S1, West Java). Populations X1 and B3 showed broad virulences to all varieties, whereas T2 was the least virulent. BPH field\u27s population had evolved into more virulence than biotype 4. Genotype resistance screening should use the BPH of this virulence population. Five BPH clusters which were further divided into 10 subclusters representing differential virulence toward 10 differential varieties were present in the tested BPH. Each virulence cluster was characterized by its ability to overcome four to eight single or double resistant genes. This BPH virulence core collection can be used in the characterization studies of candidate for resistant varieties or to form near-isogenic lines, or to study the insect and rice plant interaction

Characteristics of portuguese strains of Agrobacterium tumefaciens isolated from grapevine and stone fruit trees

Prospecções efectuadas em vinhas e pomares no País revelaram a presença do agente causal do tumor bacteriano, Agrobacterium tumefaciens. Com base no estudo das características morfológicas, culturais, bioquímicas e de patogenicidade, quarenta isolamentos de Agrobacterium spp. foram identificados e separados nos respectivos biótipos. A maioria das estirpes isoladas apresentaram características inerentes aos biótipos 1 e 2. No caso da videira, foi também detectada a presença da bactéria no translocado xilémico, o que evidencia a natureza sistémica desta doençainfo:eu-repo/semantics/publishedVersio