Authors:Judit Bíró, Noémi Erdei, Ibolya Székely, and L. Stipkovits
Increasing use of Mycoplasma gallisepticum (MG) live vaccines has led to a need for the differentiation of MG strains. The MG strains MK-7, MS-16, S6, FS-9 and R strains and the MG live vaccine strain F were compared by random amplification of polymorphic DNA (RAPD) in this study. Using RAPD, different patterns were found among the MG strains. In addition to this, we examined the differentiating potential of polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) primers targeted at the crmA, crmB, crmC, gapA, mgc2 and pvpA genes encoding cytadherence-related surface proteins. These proteins may take part in the pathogenesis of MG-induced disease. Differentiation of strain F is based on the identification of restriction enzyme sites in the PCR amplicons. Using HphI enzyme, crmC PCR amplicons produced different RFLP patterns. Digestion of amplicons of gapA-specific PCR with MboI enzyme also produced distinct patterns. Differences were observed among strains R and F by digestion of mgc2 PCR amplicons with HaeIII and VspI enzymes and digestion of pvpA PCR amplicons with AccI, PvuII and ScrFI endonucleases. This method can be used for the rapid differentiation of vaccine strain from wild strains. Differentiation of MG strains is a great advantage for diagnosticians or practitioners and it is useful for epidemiological studies.
Authors:Anna Füzy, Ibolya Biró, Ramóna Kovács, and Tünde Takács
The characterization of mycorrhizal status in hosts can be a good indicator of symbiotic associations in inoculation experiments or in ecological research. The most common microscopic-based observation methods, such as (i) the gridline intersect method, (ii) the magnified intersections method and (iii) the five-class system of Trouvelot were tested to find the most simple, easily executable, effective and objective ones and their appropriate parameters for characterization of mycorrhizal status. In a pot experiment, white clover (Trifolium repens L.) host plant was inoculated with 6 (BEG144; syn. Rhizophagus intradices) in pumice substrate to monitor the AMF colonization properties during host growth. Eleven (seven classical and four new) colonization parameters were estimated by three researchers in twelve sampling times during plant growth. Variations among methods, observers, parallels, or individual plants were determined and analysed to select the most appropriate parameters and sampling times for monitoring. The comparability of the parameters of the three methods was also tested. As a result of the experiment classical parameters were selected for hyphal colonization: colonization frequency in the first stage or colonization density in the later period, and arbuscular richness of roots. A new parameter was recommended to determine vesicule and spore content of colonized roots at later stages of symbiosis.
Authors:Susan Szathmáry, Nandani Rajapakse, Ibolya Székely, E. Pitlik, Judit Bíró, Noémi Erdei, and L. Stipkovits
The capture of mycoplasmas (M. hominis, M. buccale, M. fermentans, M. bovis, M. synoviae, M. gallisepticum and M. arthritidis) based on lipid structures and adhesion molecules present in the mycoplasmal membrane was tested using different chromatographic resins (ActiClean Etox, ClarEtox, Heparin-Actigel, Sulfated Hiflow and SulfEtox). All of the resins efficiently reduced mycoplasma concentrations in Phosphate Buffered Saline (PBS) and in Fetal Bovine Serum (FBS) by 3-8 logs in a few minutes. This technology could be used for removing mycoplasmas from tissue culture components such as serum, and for concentrating mycoplasmas in vaccine production.