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VolumeVolume 2.1, 20102010 ”Fusariosaurus” - The Discovery of a New Organism? Fusariosaurus ......................p2 Photo Competition ...........p2 Fusarium ............................... p3 Fusariosaurus in Wheat Campylobacter Overview ............................. p5 More about Campylobacter ................... p6 T410026.indd 1 1/5/2010 12:29:02 PM 2 Fusariosaurus (cover) By Jvo Siegrist, Product Manager Microbiology…. [email protected] Who says that scientists don’t have a sense of humor? The interesting and intriguing microscopic image on the riosaurus”, based on the Pterosaurs which dominated the skies front cover of this issue of Microbiology Focus is the winning during the mesozoic era (late Triassic to the end of the Creta- photo from the Summer 2009 Fluka Microbiology Photo ceous period; 220 to 65.5 million years ago). Competition. It captures a fungus of the species Fusarium Dr. Ela Suchowilska is an expert on Fusarium and wrote an culmorum with a notable example of a typical mycel-formed interesting article in this issue of Microbiology Focus. To learn conidia with spores that have already germinated. Germ tubes, more about this noteworthy topic, see “Dangerous Fungi of the visible on image, develop later to abundant mycelium. Espe- Genus Fusarium”. cially amusing was the description provided by Dr. Ela Su- chowilska for that unique photo. She titled the image “Fusa- Figure 1: Pterosaurs Figure 2: “Fusariosaurus” Winning Entries of Photo Competition Last summer we held our Fluka Micro- prizes are showcased below. The aim of all who entered our competition and biology Photo Competition and re- the competition was to encourage mi- also our independent jury members Dr. ceived some fascinating images from crobiologists to promote their work, Antje Breitenstein (Scanbec GmbH), around the world. The photographic with the condition that entries should Prof. Dr. Corinne Gantenbein (ZHSW), entry winning Best of Show is featured illustrate any microorganisms (living or and Prof. Dr. Mohammad Manafi (Med- in the previous article. The entries win- dead) or a microbiologist in action at ical University of Vienna). ning second, third, and fourth place work. Sigma-Aldrich would like to thank Second Place Winner: Third Place Winner: Fourth Place: This is the 1000X Microscopic view of two isolates Typical colony of Mycobacterium tuberculosis “Jogging with germinating Fusarium culmorum from Indian Ocean nodules capable of metal seen under a microscope with 10x magnifi cation. conidia” oxidation from its sulphides and oxides. Abhilash Pillai Martin Anandi Ela Suchowilska National Metallurgical Laboratory, India Institute of Tropical Medicine, Antwerp, Belgium University of Warmia and Mazury in Olsztyn, Poland sigma-aldrich.com/microbiology T410026.indd 2 1/5/2010 12:29:09 PM 3 Dangerous Fungi of the Genus Fusarium By Dr. Ela Suchowilska, Department of Plant tant consideration and the main goal of numerous breeding programs across the Breeding & Seed Production, University of world. This disease has been increasing in incidence and severity in recent years, due Warmia and Mazury in Olsztyn-Poland…. to the implementation of simplifi ed crop production technologies including intensive [email protected] monoculture systems and simplifi ed crop rotation (in particular with respect to wheat Fungi are heterotrophic organisms that and maize), the lack of eff ective fungicides for Fusarium control and the absence of were previously included in the King- resistant varieties (Mesterhazy 2002). Therefore, the current direction of research dom Plantae, and today are classifi ed as studies is to develop new, Fusarium-resistant varieties that could be relied on as a safe a separate kingdom, MYCOTA. The source of food for humans and animals. Kingdom Fungi comprises unicellular organisms (e.g. yeasts), molds (e.g. Mycotoxins Fusarium species fungi of the genera Aspergillus, Penicil- Type A trichothecenes (e.g. T2-toxin, HT-2 toxin, diacetoxyscirpenol) Fusarium sporotrichioides, F. poae, F. graminearum, F. culmorum, and type B trichothecenes (e.g. deoxynivalenol and its acetyl F. crookwellense, F. acuminatum lium, Fusarium) and the Basidiomycetes, derivatives, nivalenol) including the well-known edible and Fumonisins F. moniliforme, F. proliferatum Zearalenone F. graminearum, F. culmorum, F. crookwellense poisonous cap mushrooms. Molds are Cyclodepsipeptides (enniatins, beauvericin) F. avenaceum. F. sporotrichioides composed of fi lamentous hyphae that Table 1: Most common mycotoxins produced by Fusarium species, found in infected grain (Nelson 1993). form an interconnected network known as mycelium, on which species-specifi c The programs aimed to breed Fusarium-resistant varieties involve determining patho- spores of the imperfect stage (most gen-host interactions, the types and mechanisms of resistance, as well as genes respon- often asexual conidiospores) are pro- sible for resistance to fungi of the genus Fusarium. Due to the low host specifi city of duced, sometimes accompanied by these pathogens, FHB resistance is conferred by multiple genes (Parry et al., 1995). sexual spores. Their typical size is from Mesterhazy (2002) reported fi ve diff erent types of resistance to FHB, i.e. resistance to several to several dozen micrometers, initial infection (type I), resistance to the spread of the pathogen (type II), ability to de- so they are referred to as “microscopic grade mycotoxins (type III), resistance to kernel infection (type IV), and tolerance (type fungi”, since their structures can only V). FHB resistance may be conditioned phytochemically by the presence of phenolic be seen under the microscope. compounds inhibiting mycelial growth in host tissues. An analysis of their concentrations Fungi of the genus Fusarium are of great could facilitate the selection of resistant varieties (Suchowilska 2008). economic significance due to their Recent research has greatly expanded our knowledge about the role of fusariotoxins widespread occurrence and high in pathogenesis and their impact on humans and animals. The presence of the above pathogenicity to all crop species grown metabolites in the human food chain is a serious worldwide concern. Trichothecenes throughout the world. This is of par- are known to act by blocking protein biosynthesis in the cell. The phytotoxic eff ects ticular importance in the case of cereals, of trichothecenes, mostly DON and NIV, have been demonstrated in a number of as head and kernel infections may dras- experiments, but their role in pathogenesis seems to be most signifi cant. A relation- tically reduce grain yield and quality. ship has been found between the FHB resistance of crops and the accumulation of Fusarium head blight (FHB), caused by fusariotoxins, particularly DON. Although DON does not necessarily cause typical FHB approximately 16 species of the genus symptoms, the fungi that produce this toxin are usually highly virulent. The presence Fusarium (Parry et al. 1995), can be of DON also contributes to the spread of the fungus within the spike. NIV-producing devastating, with an overall decrease in chemotypes are less aggressive than DON-producing chemotypes (Miedaner and yield reaching 70%. In addition, toxic Reinbrecht, 2001). Many programs have been initiated to prevent and reduce myco- secondary metabolites produced by toxin contamination of wheat and other cereals. The co-occurrence of multiple my- Fusarium species can be found in FHB- cotoxins can produce a combined synergistic eff ect. Resistant cereal lines inoculated affected grain. The most common with pathogens of the genus Fusarium contained lower concentrations of DON in the among them are trichothecenes (most- grain than susceptible cultivars (Miller et al.,1985, Mirocha et al., 1994). Harris et al. ly type B, deoxynivalenol and nivalenol) (1999) reported that the trichothecenes (especially DON) may act as virulence factors (Ueno 1977, Joff e 1986), zearalenone, to enhance the spread of F. graminearum on maize. Cultivars, breeding strains and fumonisins and other fusariotoxins lines show a great variability in susceptibility to infection, which is refl ected in various (Nelson 1993) (Table 1). The above sub- levels of yield reduction in diff erent traits (Wiśniewska et al., 2004). Contemporary stances exhibit very strong phytotoxic common wheat cultivars are all susceptible to Fusarium infection to a greater or and zootoxic eff ects. The development lesser extent (Mesterhazy et al.,1999). The ingestion of food containing trichothecenes of FHB-resistant varieties is an impor- may induce numerous diseases termed mycotoxicoses whose symptoms resemble sigma-aldrich.com/microbiology T410026.indd 3 1/5/2010 12:29:26 PM 4 Figure 1: FHB symptoms- fi eld experiments with Figure 2: FHB symptoms, zoomed Figure 3: Fusarium culmorum mycelium on agar Fusarium culmorum infection of spring wheat plate those of radiation sickness, including References 1. Harris LJ, Desjardins AE, Plattner RD, Nicholson P, Butler G, Young, JC, 7. Nelson P. E. 1993. Fumonisins, Mycotoxins Produced by Fusarium diarrhea, vomiting, nausea, leucocyto- Weston G, Proctor RH and Hohn TM. 1999. Possible role of trichoth- Species: Biology, Chemistry and Signifi cance. Phytopathology, 31: sis (Alimentary Toxic Aleukia– ATA), ecene mycotoxins in virulence of Fusarium graminearum on maize. 233-252 Plant Dis 83:954-960. 8. Parry D.W., Jenkinson, P. and McLeod L. 1995. Fusarium ear bleeding in the gastrointestinal tract, 2. Joff e A. 1986. Fusarium species. Their Biology

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