soil viruses pdf

Infiltration of viruses through soil columns, their soil surface run‐off and their survival in soils were evaluated for various viruses, including coliphage, echoviruses, polioviruses, coxsackieviruses and rotavirus (e.g. (1979) Soil Survival, adsorption, movement, factors affecting survival. J Microbiol 46:364–372, Prigent M, Leroy M, Confalonieri F et al (2005) A diversity of bacteriophage forms and genomes can be isolated from the surface sands of the Sahara desert. This is a preview of subscription content, Ackermann H-W (2007) 5550 phages examined in the electron microscope. Environ Microbiol 9:2563–2574. Here is an example ... pdf, . Mol Plant Pathol 10:115–128, Prestel E, Salamitou S, DuBow MS (2008) An examination of the bacteriophages and bacteria of the Namib desert. FEMS Microbiol Ecol 15:99–107, McDaniel LD, Young E, Delaney J et al (2010) High frequency of horizontal gene transfer in the oceans. Examination of purified virus particles via TEM revealed four major morphological types of mangrove soil viruses, that is, non-tailed spherical viruses and three types of tailed viruses (myoviruses with contractile tails, sipho-viruses with long and non-contractile tails and podo-viruses with short tails) (Additional file 1: … This service is more advanced with JavaScript available, Interactions in Soil: Promoting Plant Growth Biol Fertil Soils 49(7):857–869. doi: Winter C, Weinbauer MG (2010) Randomly amplified polymorphic DNA reveals tight links between viruses and microbes in the bathypelagic zone of the northwestern Mediterranean sea. Microbiology 157:919–936, Juhala RJ, Ford ME, Duda RL et al (2000) Genomic sequences of bacteriophages HK97 and HK022: pervasive genetic mosaicism in the lambdoid bacteriophages. Appl Environ Microbiol 69:285–289, Barker H, Reavy B, McGeachy KD et al (1998) Transformation of, Barrett JE, Virginia RA, Hopkins DW et al (2006) Terrestrial ecosystem processes of Victoria Land, Antarctica. In nearly every reported case for aquatic and porous media environments (soils and sediments) viral abundance exceeds that of co-occurring host populations by 10–100-fold. Environ Microbiol 12:642–648. Deep Sea Res II 49:827–845, Haaber J, Middelboe M (2009) Viral lysis of, Hashem FM, Angle JS (1988) Rhizobiophage effects on, Hashem FM, Angle JS (1990) Rhizobiophage effects on nodulation, nitrogen fixation, and yield of field-grown soybeans (, Heldal M, Bratbak G (1991) Production and decay of viruses in aquatic environments. 2,459 soil bacteria stock photos, vectors, and illustrations are available royalty-free. Curr Opin Microbiol 12:582–587, Vassilakos N, Bem F, Tzima A et al (2008) Resistance of transgenic tobacco plants incorporating the putative 57-kDa polymerase read-through gene of Tobacco rattle virus against rub-inoculated and nematode-transmitted virus. Nepoviruses, a unique group of viruses that are transmitted among roots by soil-inhabiting nemtodes, cause grapevine fanleaf degeneration and decline. Although most of our information about viral communities comes from marine … These keywords were added by machine and not by the authors. Methods Microbiol 30:105–125, Pearson MN, Beever RE, Boine B et al (2009) Mycoviruses of filamentous fungi and their relevance to plant pathology. Microb Ecol 56:437–447, Williamson KE, Helton RR, Wommack KE (2012) Bias in bacteriophage morphological classification by transmission electron microscopy due to breakage or loss of tail structures. Methods Enzymol 421:259–268, Casjens S (1998) The diverse and dynamic structure of bacterial genomes. virus. Viruses are omnipresent and extraordinarily abundant in the microbial ecosystems of water, soil, and sediment. Science 330:50, McGrath S, van Sinderen D (2007) Bacteriophage: genetics and molecular biology. The log reduction of each virus was cal-culated by the formula ‘‘log 10 N/N 0’’ where N is the titer of the virus at the specified day and N 0 is the virus … You probably don’t need to sterilize your soil if you don’t have any pests or diseases. Viruses - rare, thankfully, and most require living plant tissue to survive, but they can also hitch a ride on fungi or nematodes and flow in on water. Duboise et al. Specifically, people are panicking over the risk of contracting Legionnaires disease from potting mix. Appl Environ Microbiol 74:5975–5985, King AMQ, Adams MJ, Carstens EB et al (eds) (2011) Ninth report of the international committee on taxonomy of viruses. Science 325:833, Weinbauer MG, Peduzzi P (1995) Significance of viruses versus heterotrophic nanoflagellates for controlling bacterial abundance in the northern Adriatic Sea. Mol Plant Pathol 4:211–215, Mann NH, Cook A, Millard A et al (2003) Bacterial photosynthesis genes in a virus. Trends Microbiol 18:11–19, Kühne T (2009) Soil-borne viruses affecting cereals – known for long but still a threat. Extremophiles 9:289–296, Reavy B, Arif M, Kashiwazaki S et al (1995) Immunity to Potato mop-top virus in, Rohwer F, Thurber RV (2009) Viruses manipulate the marine environment. Consequently, viruses are major players in global geochemical cycles, influencing the turnover and concentration of nutrients and gases. J Plankton Res 17:1851–1856, Williamson KE, Radosevich M, Wommack KE (2005) Abundance and diversity of viruses in six Delaware soils. Soil profiles reveal soil horizons, which are fundamental genetic layers, weathered into underlying parent materials, in response to leaching and organic matter decomposition. Duboise et al. Thus aphid transmission often occurs without direct observation of aphid presence. It is non-persistently transmitted by a number of aphid species, so even a brief feeding episode is sufficient for virus transmission. doi: Suslow TV, Schroth MN (1982) Rhizobacteria of sugar beets: effects of seed application and root colonization on yield. Other viruses can infect microorganisms in the soil and thus affect soil microbial functioning. hops. While the ASFV genome was found in environments around infected farms, data on the virus survival in soil are scarce. Learn how to effectively treat soil-borne diseases. Recently there’s been a surge in concern over harmful bacteria in soil. doi: Thingstad TF (2000) Elements of a theory for the mechanisms controlling abundance, diversity, and biogeochemical role of lytic viruses in aquatic systems. Appl Environ Microbiol 71:3119–3125, Williamson KE, Radosevich M, Smith DW et al (2007a) Incidence of lysogeny within temperate and extreme soil environments. At least 14 species of aphids transmit the virus from infected to healthy plants in sap that clings to their mouthparts . Soil Biol Biochem 38:3120–3140, Hosseinidoust Z, Tufenkji N, van de Ven TGM (2013) Predation in homogenous and heterogenous phage environments affects virulence determinants of, Hull R (2002) Matthews’ plant virology, 4th edn. In the presence of protein, some infectious virus may survive for 7 days at pH 13.4 and for several hours below pH 4.0 (49). Tobacco Mosaic and Tomato Mosaic Viruses are extremely stable and can survive for years in soil, Trends Microbiol 13:278–284, Breitbart M, Salamon P, Andresen B et al (2002) Genomic analysis of uncultured marine viral communities. 1985). Understanding African swine fever virus (ASFV) transmission is essential for strategies to minimize virus spread during an outbreak. Cite as. J Mol Biol 299:27–51, Keel C, Ucurum Z, Michaux P et al (2002) Deleterious impact of a virulent bacteriophage on survival and biocontrol activity of, Kim K-H, Chang H-W, Nam Y-D et al (2008) Amplification of uncultured single-stranded DNA viruses from rice paddy soil. J Biol Chem 284:12599–12603, Lee K-M, Yu J, Son M et al (2011) Transmission of, MacFarlane SA (2003) Molecular determinants of the transmission of plant viruses by nematodes. Res Microbiol 164:17–21, Guixa-Boixereu N, Vaqué D, Gasol JP et al (2002) Viral distribution and activity in Antarctic waters. FEMS Microbiol Lett 236:249–256, Brown DJF, Robertson WM, Trudgill DL (1995) Transmission of viruses by plant nematodes. Soil Biol Biochem 38:3019–3034, Bekal S, Domier LL, Niblack TL et al (2011) Discovery and initial analysis of novel viral genomes in the soybean cyst nematode. Another consideration is that viral pathogenesis of soil microorganisms can contribute to recycling of nutrients within soil microbial populations. Annu Rev Phytopathol 33:223–249, Brussow H, Kutter E (2005) Phage ecology. That is as much mass as two cows per acre. Limnol Oceanogr 45:1320–1328, Thingstad TF, Lignell R (1997) Theoretical models for the control of bacterial growth rate, abundance, diversity and carbon demand. ... fungi, parasitic worms (helminths), and viruses… Soils could contain in excess of 108 virus particles/gram of soil and this wide variety of viruses can affect plant growth in many different ways. Quantitative aspects of the transmission of African swine fever. Seeley and Primrose (1982) Natural environments Concentration, isolation. Most are decomposers that consume simple carbon compounds, such as root exudate… Course and transmission characteristics of oral low-dose infection of domestic pigs and European wild boar with a Caucasian African swine fever virus isolate, High Virulence of African Swine Fever Virus Caucasus Isolate in European Wild Boars of All Ages, View 2 excerpts, references results and methods, By clicking accept or continuing to use the site, you agree to the terms outlined in our. (1979) Soil Survival, adsorption, movement, factors affecting survival. Viruses: Soil viruses are of great importance, as they may influence the ecology of soil biological communities through both an ability to transfer genes from host to host and as a potential cause of microbial mortality. of virus-like particles counted from the different soil zones or in the percentage frequency of the different particle morphologies in each zone. Angly FE, Felts B, Breitbart M et al (2006) The marine viromes of four oceanic regions. Annu Rev Genet 32:339–377, Casjens S (2003) Prophages and bacterial genomics: what have we learned so far? We investigated different soil matrices spiked with ASFV-positive blood from infected wild boar to see if ASFV can remain infectious in the soil beneath…, Stability of African Swine Fever Virus in Carcasses of Domestic Pigs and Wild Boar Experimentally Infected with the ASFV “Estonia 2014” Isolate. Adsorption of viruses on soil particles Gerba et al. The study examined how effective different forms of heat sterilisation of soil were at inactivating three plant viruses. Soil-borne viruses that are pathogens of plants can have obvious deleterious effects. The intent behind sterilizing soil is to reduce the risk of potential harm and help get rid of fungi, viruses, diseases, weeds, and pests so that there’s less unpredictability to deal with during the gardening season. , . (1975) Soil, groundwater Fate of wastewater bacteria and viruses in soil. There were approximately 1.2 x 109 VLPs per gram of dry weight soil for each soil. viruses in soil, finds new research. While steam alone was enough to eradicate two of the viruses, the highly resilient tobacco mosaic virus required the … of virus-like particles counted from the different soil zones or in the percentage frequency of the different particle morphologies in each zone. Nat Rev Microbiol 9:722–732, Fuhrman JA (1999) Marine viruses and their biogeochemical and ecological effects. Williamson SJ, Rusch DB, Yooseph S et al (2007b) The Sorcerer II global ocean sampling expedition: metagenomic characterization of viruses within aquatic microbial samples. Limestone is best applied 3 to 6 months in advance and tilled into the garden soil. Part of Springer Nature. Nature 424:741, Marsh P, Wellington EMH (2006) Phage-host interactions in soil. the study—comparing removal of viruses and bacterial indica-tors in MBR and conventional plants—it was realized that work was needed to identify data analysis and quantification methods for interpreting enteric virus and QC data. It has become apparent in recent years that the diversity of viruses in the environment is much greater than that inferred from known viruses which are predominately pathogens of humans and of organisms important to man. The virus may spread to daughter tubers when infected tubers are used as seed (Crosslin et al., 1999). These plant viruses can exist either freely or in association with soil-inhabiting vector organisms such as nematodes or other microorganisms. Sullivan MB, Lindell D, Lee JA (2006) Prevalence and evolution of core photosystem II genes in marine cyanobacterial viruses and their hosts. Microsc Res Tech 75:452–457. virus genomes from metagenomic datasets is lacking and thus, the genetic diversity of giant viruses remains underexplored. Physico-chemical and bacteriological parameters measured in the soils tested Sandy topsoil (rice fields) Building sand Soil-based compost Microbiological analysis Total aerobic plate count at 37°C, 24h (CFU/mL) 2.00 102 8.00 4 5 viruses, bacteria and antibiotic resistance Fast Activities (to do during the lesson) » Balloon Popping Exercise: To demonstrate germ transmission with an uncovered sneeze. Not logged in • Nematodes. Bacteria fall into four functional groups. Epidemiological considerations on African swine fever in Europe 2014–2018, African swine fever: a global view of the current challenge, Laboratory‐scale inactivation of African swine fever virus and swine vesicular disease virus in pig slurry. Ecology of soil bacteriophages. The final two entries in the Top 10 at positions 5 and 8, Potato virus Y (PVY) and Plum pox virus (PPV), respectively, are both from one of the largest families of plant viruses, the Potyviridae, also containing many of the most economically significant viruses. A variety of classic and emerging soil-related bacterial and fungal pathogens cause serious human disease that frequently presents in primary care settings. might adsorb virus. Bacteria are tiny, one-celled organisms – generally 4/100,000 of an inch wide (1 µm) and somewhat longer in length. Seeley and Primrose (1982) Natural environments Concentration, isolation. We shed light on their coding potential and expand the phylogenetic framework of the NCLDV. Adv Virus Res 86:327–350, Campbell RN (1996) Fungal transmission of plant viruses. Proc R Soc Lond B 271:565–574, Breitbart M, Miyake JH, Rohwer F (2004b) Global distribution of nearly identical phage-encoded DNA sequences. Understanding African swine fever virus (ASFV) transmission is essential for strategies to minimize virus spread during an outbreak. An example of a young hop rhizome. Viruses do more than just make us sick. It is non-persistently transmitted by a number of aphid species, so even a brief feeding episode is sufficient for virus transmission. CRC Press, Washington, DC, pp 129–163, Brussow H, Canchaya C, Hardt W-D (2004) Phages and the evolution of bacterial pathogens: from genomic rearrangements to lysogenic conversion. Viruses and viroids also can be transmit-ted through seed, vegetative prop-agation and pruning (Figure 5). Proc Natl Acad Sci U S A 99:10494–10499, Danovaro R, Dell’Anno A, Corinaldesi C et al (2008) Major viral impact on the functioning of benthic deep-sea ecosystems. See soil bacteria stock video clips. Res Microbiol 159:349–357, Stephens PM, O’Sullivan M, O’Gara F (1987) Effect of bacteriophage on colonization of sugarbeet roots by fluorescent, Steward GF, Wikner J, Smith DC et al (1992) Estimation of virus production in the sea. Arch Virol 152:227–243, Allen B, Willner D, Oechel WC et al (2010) Top-down control of microbial activity and biomass in an Arctic soil ecosystem. The majority of nematodes are soil dwelling animals and move with soil. While the ASFV genome was found in environments around infected farms, data on the virus survival in soil are scarce. Viruses, Nematodes, Mycoplasmas and Spiroplasmas Host Susceptible-crop-cultivar Favorable Environment Air temperature Soil fertility Rainfall Soil temperature Soil type Relative humidity Soil pH Soil moisture Disease Plant Disease Triangle You are currently offline. Therefore, methods for quantifying viruses, qualifying results, and apply- Science 332:106–109, Gonzalez-Martin C, Teigell-Perez N, Lyles M et al (2012) Epifluorescent direct counts of bacteria and viruses from topsoil of various desert storm regions. Tubers from soil with a history of tobacco rattle virus serve as a reservoir. Nat Rev Microbiol 3:504–510, Felix M-A, Ashe A, Piffaretti J et al (2011) Natural and experimental infection of, Fierer N, Breitbart M, Nulton J et al (2007) Metagenomic and small-subunit rRNA analyses reveal the genetic diversity of bacteria, archaea, fungi and viruses in soil. Abstract. Try these curated collections. Some features of the site may not work correctly. ASFV can survive for extended time periods in animal products, carcasses, and the environment. Elsevier, San Diego, Kristensen DM, Mushegian AR, Dolja VV et al (2009) New dimensions of the virus world discovered through metagenomics. The hop plant survives over‑winter as a dormant rhizome. This process is experimental and the keywords may be updated as the learning algorithm improves. We looked for the presence of viruses in soils from the Garwood dry valley in Antarctica. Abundance appears to be strongly influenced by water availability and temperature, but a lack of informational standards creates difficulties for cross-study analysis. Viruses, Nematodes, Mycoplasmas and Spiroplasmas Host Susceptible-crop-cultivar Favorable Environment Air temperature Soil fertility Rainfall Soil temperature Soil type Relative humidity Soil pH Soil moisture Disease Plant Disease Triangle To investigate the mangrove soil viral community structure and to reveal the genetic and functional diversity of mangrove soil viruses, six soil samples were collected from three different mangrove habitats (bay, river and port) in two distant areas (Guangxi and Hainan Provinces, China) for a period of 2 years (2015 October–2017 March) (Fig. Ecology of soil bacteriophages. PLoS Biol 4(11):e368. © 2020 Springer Nature Switzerland AG. Transgenic Res 17(5):929–941, Vos M, Birkett PJ, Birch E et al (2009) Local adaptation of bacteriophages to their bacterial hosts in soil. ASFV can survive for extended time periods in animal products, carcasses, and the environment. PDF | As abundant members of microbial communities, viruses impact microbial mortality, carbon and nutrient cycling, and food web dynamics. Nature 459:207–212, Santala J, Samuilova O, Hannukkala A et al (2010) Detection, distribution and control of Potato mop-top virus, a soil-borne virus, in northern Europe. Proc Natl Acad Sci U S A 99:14250–14255, Breitbart M, Felts B, Kelley S et al (2004a) Diversity and population structure of a near-shore marine-sediment viral community. Here we describe 16 giant virus genomes from a forest soil ecosystem that were recovered using a cultivation-independent approach. J Gen Virol 92:1870–1879, Breitbart M, Rohwer F (2005) Here a virus, there a virus, everywhere the same virus? Metatranscriptomic reconstruction reveals RNA viruses with the potential to shape carbon cycling in soil Evan P. Starra, Erin E. Nucciob, Jennifer Pett-Ridgeb, Jillian F. Banfieldc,d,e,f,g,1, and Mary K. Firestoned,e,1 aDepartment of Plant and Microbial Biology, University of California, Berkeley, CA 94720; bPhysical and Life Sciences Directorate, Lawrence Livermore What bacteria lack in size, they make up in numbers. Soil viruses are abundant (∼10 7 to 10 9 viruses per gram ), and we already have evidence for direct and indirect viral impacts on soil microbiota and biogeochemistry (4 – 8). Microbiol Mol Biol Rev 68:560–602, Bushman F (2002) Lateral gene transfer: mechanisms and consequences. Nature 452:629–632, Edwards RA, Rohwer F (2005) Viral metagenomics. Nature 399:541–548, Ghosh D, Roy K, Williamson KE et al (2008) Prevalence of lysogeny among soil bacteria and presence of 16S rRNA and, Gómez P, Buckling A (2011) Bacteria-phage antagonistic coevolution in soil. Soil Profiles Soil profiles are two-dimensional slices or exposures of soils like we can view from a road cut or a soil pit. Semantic Scholar is a free, AI-powered research tool for scientific literature, based at the Allen Institute for AI. The most common among these viruses are grapevine fanleaf virus (GFLV), tobacco ringspot virus (TRSV), and tomato ringspot virus (ToRSV). Epidemiology of African swine fever virus. Virus Res 141:174–183, Lang AS, Beatty JT (2006) Importance of widespread gene transfer agent genes in α-proteobacteria. A teaspoon of productive soil generally contains between 100 million and 1 billion bacteria. Academic, London, Jarrell KF, Walters AD, Bochiwal C et al (2011) Major players on the microbial stage: why archaea are important. Not affiliated Most plant viruses are either rod-shaped or isometric (polyhedral). The virus can also be spread mechanically. The virus is usually detectable when symptoms are seen but may also be present in asymptomatic tissue (Charlton, 2006). Mar Microbial Food Webs 6:57–78, Stewart FM, Levin BR (1984) The population biology of bacterial viruses: why be temperate. 13 Plant virus status 41 Websites 13 Exotic pests and diseases ... soil level new shoot old stem new root Figure 1. Williamson KE, Corzo KA, Drissi CL (2013) Estimates of viral abundance in soils are strongly influenced by extraction and enumeration methods. This region is extremely cold, Microbiol Mol Biol Rev 74:42–57, © Springer Science+Business Media Dordrecht 2014, Interactions in Soil: Promoting Plant Growth, Hops. fungi, which introduce the virus or viroid during feeding. Results and Discussion Table 1 shows the survival in days of the three viruses in the test waters. doi: Williamson KE, Schnitker JB, Radosevich M et al (2008) Cultivation-based assessment of lysogeny among soil bacteria. Viral abundance in soils can range from below detection limits in hot deserts to over 1 billion per gram in wetlands. Viral pathogenesis of soil microorganisms can have obvious positive or negative effects depending on whether the affected microorganism is beneficial or deleterious to plant growth. We looked for the presence of viruses in soils from the Garwood dry valley in Antarctica. Soil Viruses: A New Hope Joanne B. Emersona aDepartmentofPlantPathology,UniversityofCalifornia,Davis,Davis,California,USA ABSTRACT As abundant members of microbial communities, viruses impact micro- bial mortality, carbon and nutrient cycling, and food web dynamics. Typically, the growth of these microorganisms is favored by particular soil characteristics and may involve complex life cycles including amoebae or animal hosts. Over 10 million scientific documents at your fingertips. doi: Ashelford KE, Day MJ, Fry JC (2003) Elevated abundance of bacteriophage infecting bacteria in soil. Theor Popul Biol 26:93–117. Understanding African swine fever virus (ASFV) transmission is essential for strategies to minimize virus spread during an outbreak. Viruses consist of an inner core of nucleic acid (either ribonucleic acid [RNA] or deoxyribonucleic acid [DNA]) surrounde… Res Microbiol 154:237–243, Frost LS, Leplae R, Summers AO et al (2005) Mobile genetic elements: the agents of open source evolution. Appl Environ Microbiol 73:7059–7066, Filée J, Forterre P, Laurent J (2003) The role played by viruses in the evolution of their hosts: a view based on informational protein phylogenies. Thus aphid transmission often occurs without direct observation of aphid presence. Swanson MM, Reavy B, Makarova KS et al (2012) Novel bacteriophages containing a genome of another bacteriophage within their genomes. Adsorption of viruses on soil particles Gerba et al. Aquat Microb Ecol 13:19–27, Thurber R (2009) Current insights into phage biodiversity and biogeography. African swine fever virus (ASFV) is the only virus in the Iridoviridae family which is known to infect mammals. An important effect that viruses can have on microbial populations is by mediating horizontal gene transfer and metagenomic approaches are beginning to give an understanding of potentially how widespread and important this process may be in facilitating the responses of microbial populations to environmental changes. Contaminated Soil and Transmission of Influenza Virus (H5N1) Technical Appendix Technical Appendix Table. Mol Microbiol 49:277–300, Chibani-Chennoufi S, Bruttin A, Dillman M-L et al (2004) Phage-host interaction: an ecological perspective. Trends Microbiol 15:54–62, Lawrence CM, Menon S, Eilers BJ et al (2009) Structural and functional studies of archaeal viruses. Soil-borne diseases affect all types of plants and can be a real problem in the vegetable garden. ASFV survives over a wide range of pH values and is particularly resistant to alkaline conditions. Ann Appl Biol 155:51–60. Nature 437:356–361, Suttle CA (2007) Marine viruses–major players in the global ecosystem. Nature 454:1084–1088, Dinsdale EA, Edwards RA, Hall D et al (2008) Functional metagenomic profiling of nine biomes. PLoS One 7(7):e40683. Caister Academic Press, Norfolk, Ortmann AC, Suttle CA (2005) High abundance of viruses in a deep-sea hydrothermal vent system indicates viral mediated microbial mortality. In the soil they can infect bacteria and other organisms that carry out important ecosystem functions, like nutrient cycling. transmitted through various environments (water, sewage, soil, air, or sur-faces) or food and persist enough in these vehicles to represent a health threat. J Bacteriol 186:3677–3866, Curtis TP, Sloan WT, Scannell JW (2002) Estimating prokaryotic diversity and its limits. In agricultural soil-based studies, most observations on autochthonous viruses have been performed in dry soils [19,20,21], while paddy soils have long been neglected.However, in the paddy soil, wet–dry cycling changes soil pH and nutrient availability [22,23], and also promotes the level of connectivity across aggregates, and thus increases the chance of microbial encounters [].

Interview Questions About Adapting To Change, Virtual Presence Quotes, Sic Meaning Slang, Creative Logo Template, Baked Grouper In Foil, Best 3d Puzzles, 2019 Air Force Outstanding Unit Award, Thyrsis Is A Pastoral Elegy On The Death Of,

Leave a Reply

Your email address will not be published.