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2013

A. A. Shukla, U. Gottschalk

Trends in Biotechnology (2012) 1-8

The manufacture of protein biopharmaceuticals is conducted under current good manufacturing practice (cGMP) and involves multiple unit operations for upstream production and downstream purification. Until recently, production facilities relied on the use of relatively inflexible, hard-piped equipment including large stainless steel bioreactors and tanks to hold product intermediates and buffers. However, there is an increasing trend towards the adoption of single-use technologies across the manufacturing process. Technical advances have now made an end-to-end single-use manufacturing facility possible, but several aspects of single-use technology require further improvement and are continually evolving. This article provides a perspective on the current state-of-the-art in single-use technologies and highlights trends that will improve performance and increase the market penetration of disposable manufacturing in the future.

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M. Li, Y. X. Qiu

Vaccine 31 (2013) 1264-1267

An effective downstream bio-processing of vaccine products requires complete chemical knowledge of the contaminants that may arise from a given vector expression system. Whether the vaccine is made from the traditional egg-based or the new cell-cultured process, it is the expression system that determines the types of impurities that need to be identified and removed from the vaccine product.

There are mechanical and chemical factors that can either reduce the yield or render a vaccine product to be irreversibly inactive. The choice of equipment and solvents is therefore important in minimizing product loss, and for maintaining an efficient and optimized manufacturing process.

The frequent out-of-specification, irreproducible data and inefficiency in the manufacturing of biologics were the basis for FDA to propose the “cGMP for the 21st Century” initiative in the year of 2000. Effective 2004, the concept of quality by design (QbD) has been imposed in the manufacturing of biologics. To facilitate the implementation of QbD FDA has encouraged the use of process analytical technology (PAT). Further, FDA believes that an optimized manufacturing scheme requires one to identify and to control the variables that can negatively affect the yield and quality of the desired product, and PAT can reveal wrongful data and alert the operator for immediate correction during processing.

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M. Bartolini, I. W. Wainer, C. Bertucci, V. Andrisano

Journal of Pharmaceutical and Biomedical Analysis 73 (2013) 77-81

Adenosine nucleotides are involved as substrates or co-factors in several biochemical reactions, catalyzed by enzymes, which modulate energy production, signal transduction and cell proliferation. We here report the development and optimization of an ion exchange liquid chromatography (LC) method for the determination of ATP, ADP and AMP. This method is specifically aimed at the determination of the ATP-ase activity of human heat shock protein 90 (Hsp90), a molecular chaperone that has emerged as target enzyme in cancer therapy. Separation of the three nucleotides was achieved in a 15-min run by using a disk shaped monolithic ethylene diamine stationary phase of small dimensions (2 mm × 6 mm i.d.), under a three-solvent gradient elution mode and UV detection at 256 nm. The described direct LC method resulted highly specific as a consequence of the baseline separation of the three adenosine nucleotides and could be applied to the determination of the enzymatic activity of ADP/ATP generating or consuming enzymes (such as kinases). Furthermore, comparison of the LOD and LOQ values of the LC method with those obtained with the malachite green assay, which is one of the most used indirect screening methodologies for ATP-ase activity, showed that the LC method has a similar range of application without presenting the drawbacks related to contamination by inorganic phosphate ions and glycerol, which are present in Hsp90 commercial samples.

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F. Ibrahim, C. Andre, R. Aljhni, T. Gharbi, Y. C. Guillaume

Journal of Molecular Catalysis B: Enzymatic 94 (2013) 136-140

Acetylcholinesterase (AChE) is a serine protease that hydrolyzes the neurotransmitter acetylcholine. Here, the effects of hydroxyl radical (OH•) and nitric oxide (NO) on AChE activity were studied using a biochromatographic process. The enzyme was immobilized on an ethylenediamine (EDA) monolithic convective interaction media (CIM) disk. The AChE enzymatic mechanism was demonstrated from the chromatographic peak shape. A decrease in AChE activity was observed for each concentration of NO, while OH• dot radical formation led to an increase in the rate of enzymatic catalysis. Michaelis–Menten and Lineweaver–Burk plots were obtained in the presence or absence of the free radicals and their effects on Km and Vmax were evaluated. Our results indicated classical deactivation/activation kinetics without significant influence on the rate of substrate binding. The variation in transition state energies (ΔΔGES) induced by the free radicals indicated that a conformational change was occurring in the active site, while changes in the binding site were negligible. These results clearly demonstrate the direct role of OH• dot and NO on AChE activity and confirm the role they may play in Alzheimer's disease.

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H. G. Schwelberger, J. Feurle, F. Ahrens

Journal of Neural Transmission 120 (2013) 983-986

Diamine oxidase (DAO) was purified to homogeneity from human seminal plasma by consecutive chromatographic fractionation on heparin-sepharose, phenyl-sepharose, CIM-QA, and Superdex 200. Human seminal plasma DAO behaves electrophoretically similar to DAO proteins from other human tissues and has very similar enzymatic properties with histamine and aliphatic diamines being the preferred substrates as well as significant conversion of polyamines. The cellular source and functional importance of DAO in human semen remain to be determined.

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P. Fernandes, C. Peixoto, VM Santiago, EJ Kremer, AS Coroadinha and PM Alves

Gene Therapy (2012), 1–8

Canine adenovirus type 2 (CAV-2) vectors overcome many of the clinical immunogenic concerns related to vectors derived from human adenoviruses (AdVs). In addition, CAV-2 vectors preferentially transduce neurons with an efficient traffic via axons to afferent regions when injected into the brain. To meet the need for preclinical and possibly clinical uses, scalable and robust production processes are required. CAV-2 vectors are currently produced in E1-transcomplementing dog kidney (DK) cells, which might raise obstacles in regulatory approval for clinical grade material production. In this study, a GMP-compliant bioprocess was developed. An MDCK-E1 cell line, developed by our group, was grown in scalable stirred tank bioreactors, using serum-free medium, and used to produce CAV-2 vectors that were afterwards purified using column chromatographic steps. Vectors producedin MDCK-E1 cells were identical to those produced in DK cells as assessed by SDS-PAGE and dynamic light scatering measurements (diameter and Zeta potential). Productivities of ~109 infectious particles (IP) ml-1 and 2x103 IP per cell were possible. A downstream process using technologies transferable to process scales was developed, yielding 63% global recovery. The total particles to IP ratio in the purified product (<20:1) was within the limits specified by the regulatory authorities for AdV vectors. These results constitute a step toward a scalable process for CAV-2 vector production compliant with clinical material specifications.

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P. Gerster, E.-M. Kopecky, N. Hammerschmidt, M. Klausberger, F. Krammer, R. Grabherr, C. Mersich, L. Urbas, P. Kramberger, T. Paril, M. Schreiner, K. Nöbauer, E. Razzazi-Fazeli, A. Jungbauer

Journal of Chromatography A, 1290 (2013) 36-45(2013) 36-45

A chromatographic process based on monoliths for purification of infective baculovirus without prior concentration step has been established. Baculovirus produced in Spodoptera frugiperda cells (Sf-9) were harvested by centrifugation, filtered through 0.8 μm filters and directly loaded onto radial 1 mL anion exchange monoliths with a channel size of 1.5–2.0 μm operated at a volumetric flow rate of one bed volume per minute. Optional an epoxy monolith was used as pre-column to reduce interfering compounds and substances influencing the capacity of anion exchange monoliths for baculovirus infectious virus could be eluted with a step gradient at salt concentrations of 440 mM NaCl. Recovery of infectious virus was highly influenced by composition and age of supernatant and ranged from 20 to >99% active baculovirus. Total protein content could be reduced to 1–8% and DNA content to 38–48% in main virus fraction. Infective virus could be 52-fold concentrated within 20.5 h and simultaneously an 82-fold volume reduction was possible when loading 1150 mL (2.1 × 108 pfu/mL) onto 1 mL scale support.

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A. Steyer, I. Gutierrez-Aguire, M. Kolenc, S. Koren, D. Kutnjak, M. Pokorn, M. Poljšak-Prijatelj, N. Rački, M. Ravnikar, M. Sagadin, A. Fratnik Steyer, N. Toplak

Journal of Clinical Microbiology, November 2013

Mammalian orthoreoviruses (MRV) are known to cause mild enteric and respiratory infections in humans. They are widespread and infect a broad spectrum of mammals. We report here the first case of MRV detected in a child with acute gastroenteritis, which showed the highest similarity to MRV reported recently in European bats. Stool sample examination of the child was negative for most common viral and bacterial pathogens. Reovirus particles were identified by electron microscopic examination of both stool suspension and cell culture supernatant. The whole genome sequence was obtained with the Ion Torrent next generation sequencing platform. Prior to sequencing, stool sample suspension and cell culture supernatant were pre-treated with nucleases and/or the convective interaction media (CIM) monolithic chromatographic method to purify and concentrate the target viral nucleic acid. Whole genome sequence analysis revealed that the Slovenian SI-MRV01 isolate was most similar to MRV found in bat in Germany. High similarity was shared in all genome segments, with nucleotide and amino acid identities between 93.8-99.0% and 98.4-99.7%, respectively. It was shown that CIM monolithic chromatography alone is an efficient method for enriching the sample in viral particles before nucleic acid isolation and next generation sequencing application.

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E. Maksimova, E. Vlakh, E. Sinitsyna, T. Tennikova
J. Sep. Sci. 2013, 36, 3741–3749

Ultrashort monolithic columns (disks) were thoroughly studied as efficient stationary phases for precipitation–dissolution chromatography of synthetic polymers. Gradient elution mode was applied in all chromatographic runs. The mixtures of different flexible chain homopolymers, such as polystyrenes, poly(methyl methacrylates), and poly(tert-butylmethacrylates) were separated according to their molecular weights on both commercial poly(styrene-co divinylbenzene).
disks (12 id × 3 mm and 5 × 5 mm) and lab-made monolithic columns (4.6 id × 50 mm) filled with supports of different hydrophobicity. The experimental conditions were optimized to reach fast and highly efficient separation. It was observed that, similar to the separation of monoliths of other classes of (macro)molecules (proteins, DNA, oligonucleotides), the length of column did not affect the peak resolution.
A comparison of the retention properties of the poly(styrene-co-divinylbenzene) diskshaped monoliths with those based on poly(lauryl methacrylate-co-ethylene dimethacrylate), poly(butyl methacrylate-co-ethylene dimethacrylate), and poly(glycidyl methacrylate-co-ethylene dimethacrylate) supports demonstrated the obvious effect of surface chemistry on the resolution factor. Additionally, the results of the discussed chromatographic mode on the fast determination of the molecular weights of homopolymers used in this study were compared to those established by SEC on columns packed with sorbent beads of a similar nature to the monoliths.

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Roy N D‘Souza, Ana M Azevedo, M Raquel Aires-Barros, Nika Lendero Krajnc, Petra Kramberger, Maria Laura Carbajal, Mariano Grasselli, Roland Meyer & Marcelo Fernández-Lahore

Vol. 1, No. 5, Pharmaceutical Bioprocessing (2013)

Downstream processing is currently the major bottleneck for bioproduct generation. In contrast to the advances in fermentation processes, the tools used for downstream processes have struggled to keep pace in the last 20 years. Purification bottlenecks are quite serious, as these processes can account for up to 80% of the total production cost. Coupled with the emergence of new classes of bioproducts, for example, virus-like particles or plasmidic DNA, this has created a great need for superior alternatives. In this review, improved downstream technologies, including aqueous two-phase systems, expanded bed adsorption chromatography, convective flow systems, and fibre-based adsorbent systems, have been discussed. These adaptive methods are more suited to the burgeoning downstream processing needs of the future, enabling the cost-efficient production of new classes biomaterials with a high degree of purity, and thereby hold the promise to become indispensable tools in the pharmaceutical and food industries.

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2012

J. Lee, H. T. Gan, S. M. Abdul Latiff , C. Chuah, W. Y. Lee, Y.-S. Yang, B. Loo, S. K. Ng, P. Gagnon

Journal of Chromatography A, 1270 (2012) 162-170

We introduce a chromatography method for purification of large proteins and viruses that works by capturing them at a non-reactive hydrophilic surface by their mutual steric exclusion of polyethylene glycol (PEG). No direct chemical interaction between the surface and the target species is required. We refer to the technique as steric exclusion chromatography. Hydroxyl-substituted polymethacrylate monoliths provide a hydrophilic surface and support convective mass transport that is unaffected by the viscosity of the PEG. Elution is achieved by reducing PEG concentration. Selectivity correlates with molecular size, with larger species retained more strongly than smaller species. Retention increases with PEG size and concentration. Salts weaken retention in proportion to their concentration and Hofmeister ranking. Retention is enhanced near the isoelectric point of the target species. Virus binding capacity was measured at 9.9 × 1012 plaque forming units per mL of monolith. 99.8% of host cell proteins and 93% of DNA were eliminated. Mass recovery exceeded 90%. IgM capacity was greater than 60 mg/mL. 95% of host cell proteins were eliminated from IgM produced in protein-free media, and mass recovery was up to 90%. Bioactivity was fully conserved by both viruses and antibodies. Process time ranged from less than 30 min to 2 h depending on the product concentration in the feed stream.

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H. M. Oksanen, A. Domanska, D. H. Bamford
Virology Volume 434, Issue 2, 20 December 2012

We report anion exchange chromatographic purification method powerful for preparation of virus particles with ultra pure quality. The technology is based on large pore size monolithic anion exchangers, quaternary amine (QA) and diethylaminoethyl (DEAE). These were applied to membrane-containing icosahedral bacteriophage PRD1, which bound specifically to both matrices. Virus particles eluted from the columns retained the ir infectivity, and were homogenous with high specific infectivity. The yields of infectious particles were up to 80%. Purified particles were recovered at high concentrations, approximately 5mg/ml, sufficient for virological, biochemical and structural analyses. We also tested the applicability of the monolithic anion exchange purification on a filamentous bacteriophage phi 05_2302. Monolithic ion exchange chromatography is easily scalable and can be combined with other preparative virus purification methods.

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P. Gagnon

Journal of Chromatography A, 1221 (2012) 57-70(2012) 57-70

This article reviews technology trends in antibody purification. Section 1 discusses non-chromatography methods, including precipitation, liquid–liquid extraction, and high performance tangential flow filtration. The second addresses chromatography methods. It begins with discussion of fluidized and fixed bed formats. It continues with stationary phase architecture: diffusive particles, perfusive particles, membranes and monoliths. The remainder of the section reviews recent innovations in size exclusion, anion exchange, cation exchange, hydrophobic interaction, immobilized metal affinity, mixed-mode, and bioaffinity chromatography. Section 3 addresses an emerging trend of formulating process buffers to prevent or correct anomalies in the antibodies being purified. Methods are discussed for preventing aggregate formation, dissociating antibody-contaminant complexes, restoring native antibody from aggregates, and conserving or restoring native disulfide pairing.

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J. Subotič, K. Koruza, B. Gabor, M. Peterka, M. Barut, J. Kos, J. Brzin

Affinity Chromatography, Dr. Sameh Magdeldin (Ed.), ISBN: 978-953-51-0325-7, InTech

Proteolytic enzymes (also known as proteases, proteinases or peptidases) offer a wide range of applications. They are routinely used in detergent, leather, food and pharmaceutical industries, as well as in medical and basic research. Therefore, effective isolation procedures are of great importance. The chapter describes the use of recently discovered protease inhibitors from basidiomycetes as affinity chromatography ligands for isolating proteases. Affinity columns with serine and cysteine protease inhibitors immobilized to the natural polymer Sepharose have been prepared, the chromatography procedure optimized and used for isolating proteases from various bacterial, plant and animal sources. The cysteine protease inhibitor macrocypin showed superior characteristics as a ligand, so was selected for immobilization to CIM (Convective Interaction Media) monolithic disks. Different immobilization chemistries and process conditions were optimized to determine the best conditions for high capacity and selectivity. A very effective method for isolating cysteine proteases was developed using affinity chromatography with the fungal cysteine protease inhibitor macrocypin immobilized to a CIM monolithic disk.

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M. Žorž

ChemieXtra 3/2012 pp 30-33

Sartorius BIA Separations produziert und vertreibt kurze monolithischen Chromatografiesäulen, die auf der CIM-Convective Interaction Media-Technologie basieren. CIM-Säulen eignen sich vor allem für die Reinigung von grossen Biomolekülen wie etwa Viren (virale Vektoren und Impfstoffe), DNA (Plasmid-DNA) und grössere Proteine (Immunglobuline G und M, pegylierte Proteine). Sie weisen einzigartige Eigenschaften in Bezug auf operative Flussraten, Adsorptionsfähigkeit und Trennung grosser Biomoleküle auf. Die Säulen werden in Forschung, Labor, Pilot- und industriellen Produktionsstufen eingesetzt und sind extrem einfach zu handhaben.

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R. Milačič, D. Ajlec, T. Zuliani, D. Žigon, J. Ščančar

Talanta 101 (2012) 203-210

In human milk zinc (Zn) is bound to proteins and low molecular mass (LMM) ligands. Numerous investigations demonstrated that Zn bioavailability in human milk is for infant much higher than in cow's milk. It was presumed that in the LMM human milk fraction highly bioavailable Zn-citrate prevails. However, literature data are controversial regarding the amount of Zn-citrate in human milk since analytical procedures reported were not quantitative. So, complex investigation was carried out to develop analytical method for quantitative determination of this biologically important molecule. Studies were performed within the pH range 5–7 by the use of synthetic solutions of Zn-citrate prepared in HEPES, MOPS and MES buffers. Zn-citrate was separated on weak anion-exchange convective interaction media (CIM) diethylaminoethyl (DEAE) monolithic chromatographic column using NH4NO3 as an eluent. Separated Zn species were determined by flame atomic absorption spectrometry (FAAS) or inductively coupled plasma mass spectrometry (ICP-MS). Quantitative separation of Zn-citrate complexes ([Zn(Cit)]- and [Zn(Cit)2]4-; column recoveries 94–102%) and good repeatability and reproducibility of results with relative standard deviation (RSD±3.0%) were obtained. In fractions under the chromatographic peaks Zn-binding ligand was identified by electrospray ionization tandem mass spectrometry (ESI-MS-MS). Limits of detection (LOD) for determination of Zn-citrate species by CIM DEAE-FAAS and CIM DEAE-ICP-MS were 0.01 μg Zn mL-1 and 0.0005 μg Zn mL-1, respectively. Both techniques were sensitive enough for quantification of Zn-citrate in human milk. Results demonstrated that about 23% of total Zn was present in the LMM milk fraction and that LMM-Zn corresponded to Zn-citrate. The developed speciation method represents a reliable analytical tool for investigation of the percentage and the amount of Zn-citrate in human milk.

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T. Koho, T. Mantyla, P. Laurinmaki, L. Huhti, S. J. Butcher, T. Vesikari, M. S. Kulomaa, V. P. Hytonen

Journal of Virological Methods 181 (2012) 6-11

Recombinant expression of the norovirus capsid protein VP1 leads to self-assembly of non-infectious virus-like particles (VLPs), which are recognized as promising vaccine candidates against norovirus infections. To overcome the scalability issues connected to the ultracentrifugation-based purification strategies used in previous studies, an anion exchange-based purification method for norovirus VLPs was developed in this study. The method consists of precipitation by polyethylene glycol (PEG) and a single anion exchange chromatography step for purifying baculovirus-expressed GII.4 norovirus VLPs, which can be performed within one day. High product purity was obtained using chromatography. The purified material also contained fully assembled monodispersed VLPs, which were recognized by human sera containing polyclonal antibodies against norovirus GII.4.

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M. Rupar, M. Ravnikar, M. Tušek-Žnidarič, P. Kramberger, L. Glais, I. Gutiérrez-Aguirre

Journal of Chromatography A, 1272 (2013) 33-40(2013) 33-40

Obtaining pure virus suspensions is an essential step in many applications, such as vaccine production, antibody production, sample preparation for procedures requiring enrichment in viruses and other in vitro characterizations. Purification procedures usually consist of complex, long lasting and tedious protocols involving several ultracentrifugation steps. Such complexity is particularly evident in the case of plant viruses, where the virus needs to be isolated from the complex plant tissue matrix. Convective Interaction Media (CIM) monoliths are chromatographic supports that have been successfully utilized for the purification of large bio-molecules such as viruses, virus like particles and plasmids from various matrixes. In this study a CIM monolith based procedure was developed for the fast purification from plant tissue of the filamentous Potato virus Y (PVY) (virion size, 740 nm × 11 nm), which is one of the most important plant viruses causing great economical losses in potato production. Different mobile phases, chemistries and sample preparation strategies were tested. The presence of the virus in the chromatographic fraction was monitored with viral RNA quantification (RT-qPCR), viral protein purity estimation (SDS-PAGE) and viral particle integrity observation (transmission electron microscopy). The optimized procedure involves initial clarification steps, followed by chromatography using CIM quaternary amine (QA) monolithic disk column. In comparison to classical purification procedure involving ultracentrifugation through sucrose and caesium chloride, the developed CIM-QA purification achieved comparable yield, concentration and purity. Plant nucleic acids were successfully removed. Purification showed good reproducibility and moreover it reduced the purification time from four working days required for classic purification to a day and a half. This is the first study where a filamentous virus was purified using CIM monolithic supports. The advantages of this new purification procedure make it an attractive method in serological diagnostic tool production, which requires purified viruses for the immunization step. Moreover, the outcome of this study could serve as starting point for the improvement of the purification methods of other important filamentous viruses.

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M. M. Segura, M. Puig, M. Monfar, M. Chillon

HUMAN GENE THERAPY METHODS 23:182–197 (June 2012)

Canine adenovirus vectors (CAV2) are currently being evaluated for gene therapy, oncolytic virotherapy, and as vectors for recombinant vaccines. Despite the need for increasing volumes of purified CAV2 preparations for preclinical and clinical testing, their purification still relies on the use of conventional, scale-limited CsCl ul- tracentrifugation techniques. A complete downstream processing strategy for CAV2 vectors based on membrane filtration and chromatography is reported here. Microfiltration and ultra/diafiltration are selected for clarifi- cation and concentration of crude viral stocks containing both intracellular and extracellular CAV2 particles. A DNase digestion step is introduced between ultrafiltration and diafiltration operations. At these early stages, concentration of vector stocks with good recovery of viral particles (above 80%) and removal of a substantial amount of protein and nucleic acid contaminants is achieved. The ability of various chromatography techniques to isolate CAV2 particles was evaluated. Hydrophobic interaction chromatography using a Fractogel propyl tentacle resin was selected as a first chromatography step, because it allows removal of the bulk of contami- nating proteins with high CAV2 yields (88%). An anion-exchange chromatography step using monolithic supports is further introduced to remove the remaining contaminants with good recovery of CAV2 particles (58– 69%). The main CAV2 viral structural components are visualized in purified preparations by electrophoresis analyses. Purified vector stocks contained intact icosahedral viral particles, low contamination with empty viral capsids (10%), and an acceptable total-to-infectious particle ratio (below 30). The downstream processing strategy that was developed allows preparation of large volumes of high-quality CAV2 stocks.

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N. Mehle, M. Ravnikar

Water research 46 (2012) 4902 - 4917

The presence of plant viruses outside their plant host or insect vectors has not been studied intensively. This is due, in part, to the lack of effective detection methods that would enable their detection in difficult matrixes and in low titres, and support the search for unknown viruses. Recently, new and sensitive methods for detecting viruses have resulted in a deeper insight into plant virus movement through, and transmission between, plants. In this review, we have focused on plant viruses found in environmental waters and their detection. Infectious plant pathogenic viruses from at least 7 different genera have been found in aqueous environment. The majority of the plant pathogenic viruses so far recovered from environmental waters are very stable, they can infect plants via the roots without the aid of a vector and often have a wide host range. The release of such viruses from plants can lead to their dissemination in streams, lakes, and rivers, thereby ensuring the long-distance spread of viruses that otherwise, under natural conditions, would remain restricted to limited areas.

The possible sources and survival of plant viruses in waters are therefore discussed. Due to the widespread use of hydroponic systems and intensive irrigation in horticulture, the review is focused on the possibility and importance of spreading viral infection by water, together with measures for preventing the spread of viruses. The development of new methods for detecting multiple plant viruses at the same time, like microarrays or new generation sequencing, will facilitate the monitoring of environmental waters and waters used for irrigation and in hydroponic systems. It is reasonable to expect that the list of plant viruses found in waters will thereby be expanded considerably. This will emphasize the need for further studies to determine the biological significance of water-mediated transport.

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