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Mikroplastika (MP) se, zaradi obsežne uporabe plastike in nepravilnega ravnanja z njo, vse pogosteje sprošča v okolje. Ker ima MP nizko gostoto, maso in velikost je zelo mobilna in se z lahkoto prenaša med različnimi ekosistemi. Številne študije navajajo, da se lahko na MP adsorbirajo organska in anorganska onesnaževala ter biološke molekule. Veliko raziskav se je osredotočilo na interakcije MP z mikroorganizmi, kljub temu je trenutno malo znanega o njenih interakcijah z virusi. Zato smo v raziskovalnem delu preučevali interakcije in zmožnost adsorpcije dveh virusov (bakteriofagov), to sta T4 virus brez ovojnice in phi6 virus z membransko ovojnico, na MP. Za študij interakcij smo izbrali dve najpogosteje najdeni MP v okolju – fragmente polietilena (MPPE) in vlakna polietilen tereftalata (MPPET). Ugotovili smo, da imata na interakcije med MP in virusi znaten vpliv vrsta in struktura MP. Do adsorpcije virusov je prišlo le v primeru MPPE, kjer so prevladovale hidrofobne interakcije, medtem ko interakcij z MPPET zaradi vlaknaste strukture in razlike v hidrofobnosti ni bilo opaziti. Prav tako smo preučili nekatere parametre vpliva strukture in vrste virusa na adsorpcijo. Ta je bila znatno počasnejša pri virusu brez ovojnice v primerjavi z virusom z membransko ovojnico. Adsorpcija virusa z membransko ovojnico je hitreje dosegla ravnotežno koncentracijo v suspenziji. Po adsorpciji smo ovrednotili tudi infektivnost MP z adsorbiranimi virusi in ugotovili, da je bila zmožnost virusa, da po adsorpciji okuži bakterije opazna samo pri virusu brez ovojnice. Tudi pri testu stabilnosti po adsorpciji, se je virus brez ovojnice izkazal kot bolj stabilen, saj je zaradi njegove strukture bolj robusten in obstojnejši na okoljske dejavnike ter ostane infektiven tudi pri spremenjenih okoljskih pogojih. Rezultati raziskave kažejo na to, da MP v okolju lahko prevzame vlogo transportnega vektorja za prenos virusov, pri čemer je proces pogojen z vrsto in strukturo MP. Virusi, ki so na splošno bolj odporni na spremembo okoljskih pogojev, bodo tudi po adsorpciji ostali na površini MP stabilni in infektivni ter bodo zmožni okužbe organizmov v popolnoma novem okolju. Microplastics (MP) are increasingly released into the environment due to extensive plastic use and improper handling. Due to their low density, mass, and size, they are highly mobile and easily transported across different ecosystems. Numerous studies indicate that organic and inorganic pollutants, as well as biological molecules, can adsorb onto MP. Many studies focused on interaction of MP with microorganisms but less is known about their interactions with viruses. In this context, we investigated the interactions and adsorption capability of two viruses (bacteriophages), namely the T4 non-enveloped virus and phi6 virus with a membranous envelope, on MP. For the study of interactions, we selected the two most commonly found types of MP in the environment - polyethylene fragments (MPPE) and polyethylene terephthalate fibres (MPPET). It was found that the type and structure of MP significantly influence the interactions between MP and viruses. Viral adsorption occurred only in the case of MPPE, where hydrophobic interactions prevailed. While no interactions were observed with MPPET due to its fibrous structure and differences in hydrophobicity. We also examined some parameters regarding the influence of structure and virus type on adsorption. Adsorption was significantly slower for the non-enveloped virus compared to the virus with a membranous envelope. The adsorption of the envelope virus reached equilibrium concentration in the suspension more rapidly. After adsorption, we evaluated the infectivity of MP with adsorbed viruses and found that the ability of the virus to infect bacteria was only evident in the case of the non-enveloped virus. In the stability test following adsorption, the non-enveloped virus demonstrated greater stability due to its structure, being more robust and resistant to environmental factors, remaining infectious even under altered environmental conditions. The research results indicate that in the environment, MP can serve as a transport vector for the transfer of viruses to distant locations. The process is solely dependent on the type and structure of the MP. Non-enveloped viruses, which are more resistant to changes in environmental conditions, will remain stable and infectious on the surface of the MP after adsorption, thus capable of infecting organisms in a completely new environment. |
