Karel Petrzik
Academy of Sciences of the Czech Republic
Network
Latest external collaboration on country level. Dive into details by clicking on the dots.
Publication
Featured researches published by Karel Petrzik.
Virus Genes | 1998
Karel Petrzik; Vladimir Benes; Ivan Mráz; Jana Honetšlegrová-Fránová; Wilhelm Ansorge; Josef Špak
The complete DNA sequence (7876 nucleotides) of strawberry vein banding virus (SVBV) has been determined. Seven open reading frames are detected that potentially code for proteins of calculated weight 37.8; 18.3; 16.6; 56.0; 81.1; 59.0 and 12.6 kDa, respectively. Their position on the viral genome is the same as that of the corresponding proteins on the cauliflower mosaic virus (CaMV) genome. Phylogenetic analysis based on the amino acid sequence of this protein shows a closer relationship of SVBV with CaMV, figwort mosaic virus and carnation etched ring virus than with other caulimoviruses.
Archives of Virology | 2002
Karel Petrzik; Ondřej Lenz
Summary.Eight new sequences of European isolates from almond, apple, hop, prune and pear of the Apple mosaic ilarvirus (ApMV) capsid protein gene are presented. A consensus sequence was established as having 654 nucleotides (nt) and two American and two European isolates were identified to have insertions 6 to 15 nucleotides after nt position 141. The insertion resulted in the American isolate A inframeshift repaired with two point insertions 17 and 68 nt downstream. The RNA around the insertion point can potentially form a stable secondary structure with three hairpins. The insertions could stabilise this structure or could be neutral. The predicted folding of the translated protein is not influenced by the insertions or frameshift, and we speculate that the region after nt position 141 is without reasonable selection pressure and represents a hot spot for the accumulation of insertion mutations in ApMV.
European Journal of Plant Pathology | 2000
Dana Vašková; Karel Petrzik; Josef Špak
Sequences of the capsid protein gene and the preceding intergenic region of eleven isolates of prune dwarf virus from central Europe were determined. The isolates were obtained from plum, cherry and peach trees. Comparison of all sequenced isolates (including two sequences published previously) revealed high (88%) conservation of the capsid protein gene. The highest degree of identity was observed in the C-terminal half, where only 13 amino acid substitutions could be observed in contrast to the N-terminal half with 22 substitutions. No reasonable correlation between amino acid substitutions and host species and/or geographic origin of the isolates was observed. Alignment with capsid protein genes of other ilarviruses revealed apple mosaic virus, elm mottle virus, lilac ring mottle virus and prunus necrotic ringspot virus as the most related to prune dwarf virus. Unlike the isolates of related prunus necrotic ringspot virus all the isolates of prune dwarf virus shared extensive conservation of the intergenic region. Portions of RNA3 were selected for design of universal primers for PCR detection.
Plant Disease | 1998
I. Mráz; Karel Petrzik; M. Šíp; J. Fránová-Honetšlegrová
Strawberry vein banding virus (SVBV) isolates from North America, Czech Republic, Norway, and Germany were collected and their variability was determined by dot blot hybridization and confirmed by sequencing of a 431-nucleotide fragment from the middle part of the coat protein gene. Two different substitutions were found between the American and two Czech SVBV isolates, but the other isolates were identical in the compared region to the American isolate. Digoxigenin-labeled probes were prepared from these isolates and used for hybridization with polymerase chain reaction-amplified fragments of 26 Czech SVBV field isolates. No significant differences in the hybridization signal were found with any combination of samples and probes. These results show that the European isolates probably originate from a common ancestor and may have been introduced to Europe from America with planting or breeding material.
Antiviral Research | 2010
Antonín Holý; D. Pavingerová; Ivan Votruba; Vlastimila Špaková; Karel Petrzik
A new method was developed for testing antiviral compounds against plant viruses based on rapidly growing brassicas in vitro on liquid medium. This method enables exchange of media containing tested chemicals in various concentrations and simultaneous evaluation of their phytotoxicity and antiviral activity. While using ribavirin as a standard for comparison, phytotoxicity and ability of the acyclic nucleotide analogues (R)-PMPA, PMEA, PMEDAP, and (S)-HPMPC to eliminate ssRNA Turnip yellow mosaic virus (TYMV) were evaluated by this method. Double antibody sandwich ELISA and real-time PCR were used for relative quantification of viral protein and nucleic acid in plants. Ribavirin had the most powerful antiviral effect against TYMV. On the other hand, (R)-PMPA and PMEA had no antiviral effect and almost no phytotoxicity compared to the control. (S)-HPMPC and PMEDAP showed moderate antiviral effect, accompanied by higher phytotoxicity. The tested compounds can be screened within 6-9 weeks in contrast to the 6 months for traditionally used explants on solid medium. The method enables large-scale screening of potential antivirals for in vitro elimination of viruses from vegetatively propagated crops and ornamentals.
Archives of Virology | 2015
Igor Koloniuk; Lenka Hrabáková; Karel Petrzik
Beauveria bassiana is a ubiquitous entomopathogen infecting hundreds of insect species. We have determined the genomic organization and the complete nucleotide sequence of a novel virus isolated from the isolate A24 of B. bassiana. Phylogenetic analysis of the polymerase gene reveals that the virus, tentatively named Beauveria bassiana virus 1, belongs to the family Amalgaviridae and represents a distinct lineage of amalgaviruses infecting fungi.
European Journal of Plant Pathology | 2005
Karel Petrzik
Apple mosaic virus (ApMV, genus Ilarvirus) was detected in pears, a previously non-reported virus host. No symptoms were visible on the host’s leaves. Seventeen out of 22 randomly selected pear trees in Italy (Lombardy) and in three regions in the Czech Republic were ApMV-infected. All nine newly sequenced ApMV isolates from pears had a 15-nucleotide insertion in the capsid protein gene in identical position of that of apple isolates compared with isolates from hop and prunes. The insertion is the most prominent (but not essential) modification of the capsid protein gene, which results in a phylogenetic separation of ApMV isolates into three clusters. Sequence analysis data of an additional 15 isolates revealed a sequence correlation with kernelled fruit trees (apple and pear).
Virology | 2016
Karel Petrzik; Tatiana Sarkisova; Josef Starý; Igor Koloniuk; Lenka Hrabáková; Olga Kubešová
A novel dsRNA virus was identified in the mycorrhizal fungus Thelephora terrestris (Ehrh.) and sequenced. This virus, named Thelephora terrestris virus 1 (TtV1), contains two reading frames in different frames but with the possibility that ORF2 could be translated as a fusion polyprotein after ribosomal -1 frameshifting. Picornavirus 2A-like motif, nudix hydrolase, phytoreovirus S7, and RdRp domains were found in a unique arrangement on the polyprotein. A new genus named Phlegivirus and containing TtV1, PgLV1, RfV1 and LeV is therefore proposed. Twenty species of oribatid mites were identified in soil material in the vicinity of T. terrestris. TtV1 was detected in large amounts in Steganacarus (Tropacarus) carinatus (C.L. Koch, 1841) and in much smaller amounts in Nothrus silvestris (Nicolet). This is the first description of mycovirus presence in oribatid mites.
Archives of Virology | 2014
Igor Koloniuk; Mohamed H. El-Habbak; Karel Petrzik; Said A. Ghabrial
The complete nucleotide sequence and genome organization of a hypovirus from the isolate ME711 of Phomopsis longicolla was determined and compared to sequences of members of the family Hypoviridae. The genome of the hypovirus, tentatively named Phomopsis longicolla hypovirus 1 (PlHV1-ME711), was determined to be 9760 nucleotides long, excluding the 3’ poly (A) tail. The genome contains a single large open reading frame (ORF) encoding a polyprotein designated as P307. Its genomic organization is typical of members of the proposed genus Betahypovirus (Yaegashi et al. in Virus Res 165:143–50, 2012).
Biologia Plantarum | 2006
D. Hanzliková Vašková; Karel Petrzik
The variability of the Strawberry vein banding virus (SVBV) isolates was investigated. In total 267 strawberry plants from 6 European countries and North America were tested for the presence of SVBV. Only 4 plants were positive. Partial genomic sequences of the capsid protein gene of three North American SVBV isolates were determined. Only minor sequence variability (0.7 %) was observed during a comparison with existing nucleotide data of the European and the North American isolates (9 isolates). No variability at all could be found in the annealing regions of primers and probes used for molecular detection of SVBV for these isolates. However, a comparison to a sequence of a Chinese isolate published recently revealed a much higher DNA sequence difference (9.5 %) of this isolate.