kingdom fungi and its classification & character

kingdom fungi

1. AGM101 FUNDAMENTALS OF MICROBIOLOGY (2+1) KINGDOM FUNGI LOGITH P 20203033067

2. INTRODUCTION The word " fungus " comes from the Latin word " mushroom .“ Fungi were found by Heinrich Anton de Bary in 1858 . The study of fungi and their particular interactions with other living things and the environment is known as mycology . Kingdom Fungi comprises a diverse group of organisms, including yeasts, molds , and mushrooms, that are crucial to ecosystems worldwide .

3. What are fungi? Fungi are the organisms that are eukaryotic,multicellular (except , Yeast ), achlorophyllous with absorptive mode of nutrition, spore-bearing and reproducing usually asexually and sexually and whose filamentous, branched somatic structures ( called hypae ) are typically surrounded by cell walls containing chitin , cellulose,or both together with many other complex carbohydrates

4. SALIENT FEATURES OF FUNGI Thallus is usually represented by a filament called Hypha, group of hyphae referred as mycelium Cell wall is mainly made up of chitin All fungi lack chlorophyll hene they are heterotrophs ,they may also saprphytes food stored in the form of glycogen Extracellular digestion takes place Fungi reproduce both sexually & Asexually

5. CLASSIFICATION

6. 1 . Reproduction: Primarily reproduce sexually through the formation of zygospores. 2 . Asexual Reproduction: They also reproduce asexually by producing sporangiospores within sporangia. 3 . Hyphae: Possess coenocytic hyphae, meaning their hyphae lack septa (cross-walls), resulting in a continuous cytoplasmic mass. 4 . Habitat : Commonly found in soil, decaying plant and animal matter, and as parasites on plants, insects, and small animals. 5 . Economic Importance: Some species are used in industrial processes like fermentation, while others can cause food spoilage. 6 . Pathogenicity : Certain species can cause infections in humans and animals, particularly in immunocompromised individuals, such as mucormycosis. 7 . Structure: Typically, their spores are produced in specialized structures called sporangia, which are borne on sporangiophores. 8 . Life Cycle : Involves a distinctive zygosporangium stage where two compatible hyphae meet and form a thick-walled zygospore, which undergoes meiosis to produce haploid spores. ZYGOMYCETES

7. OOMYCETES 1 . Cell Structure: Their cell walls are primarily composed of cellulose, unlike the chitin-based cell walls of true fungi. 2 . Reproduction: - Asexual Reproduction: Typically reproduce asexually through biflagellate zoospores produced in sporangia. - Sexual Reproduction: Involves the formation of oospores through the fusion of oogonia (female structures) and antheridia (male structures). 3 . Hyphae : Have aseptate (coenocytic) hyphae, which are multinucleate and lack cross-walls. 4 . Habitat: Commonly found in aquatic environments and moist terrestrial habitats, including soil and plant surfaces. 5 . Pathogenicity: Many species are plant pathogens, responsible for diseases like downy mildew, late blight in potatoes and tomatoes (caused by Phytophthora infestans), and root rot. 6 . Economic Impact: Cause significant agricultural losses due to their pathogenicity on crops. 7 . Motile Spores: Produce motile zoospores with two different types of flagella (a tinsel-type and a whiplash-type), which is a key distinguishing feature. 8 . Life Cycle: Alternates between diploid (dominant) and haploid phases, with both sexual and asexual reproductive stages. 9 . Misclassification: Historically classified as fungi due to their filamentous growth and similar ecological niches, but molecular studies have revealed their closer relation to algae.

8. ASCOMYCETES 1 . Reproductive Structures: Named for their unique spore-bearing structures called asci (singular: ascus), which are sac-like and contain typically eight ascospores. 2 . Sexual Reproduction: Involves the formation of ascospores within the asci, which are produced inside larger fruiting bodies called ascocarps or ascomata. 3 . Asexual Reproduction: Commonly reproduce asexually by producing conidia (asexual spores) on conidiophores. 4 . Hyphae: Possess septate hyphae, meaning their hyphae are divided by cross-walls or septa. 5 . Habitat: Found in a wide range of environments, including soil, decaying organic matter, plant surfaces, and as symbionts in lichens. 6 . Diversity: Include a wide variety of forms, such as yeasts, molds, morels, truffles, and cup fungi. 7 . Economic Importance: Many species are crucial in industry for the production of antibiotics (e.g., Penicillium species), fermentation (e.g., Saccharomyces cerevisiae for baking and brewing), and as gourmet foods (e.g., truffles and morels). 8 . Pathogenicity: Some species are plant pathogens causing diseases like apple scab and Dutch elm disease, while others are human pathogens causing conditions like athlete's foot and candidiasis. 9 . Symbiosis: Form important symbiotic relationships, such as mycorrhizae with plant roots and as partners in lichens. 1 . Life Cycle: Typically involve both sexual and asexual phases, with the sexual phase being crucial for genetic recombination and diversity.

9. 1 . Reproductive Structures: Produce spores on club-shaped structures called basidia. 2 . Reproduction : Typically reproduce sexually by forming basidiospores, often on fruiting bodies like mushrooms, brackets, or puffballs. 3 . Hyphae : Have septate hyphae with complex septal structures called dolipore septa. 4 . Habitat: Found in diverse environments, including soil, wood, and plant litter. 5 . Diversity : Include mushrooms, puffballs, bracket fungi, rusts, and smuts. 6 . Economic Importance: Some species are edible (e.g., Agaricus bisporus, the common mushroom), while others are plant pathogens (e.g., rusts and smuts). 7 . Life Cycle: Typically involves a long-lived dikaryotic mycelium stage before forming fruiting bodies for spore dispersal. 8 . Ecological Role: Important decomposers of wood and leaf litter, forming crucial ecological functions in nutrient cycling. BASIDIOMYCETES

10. 1 . Reproduction: Known for their lack of a sexual reproduction stage (teleomorph); reproduce asexually by producing conidia. 2 . Hyphae: Typically have septate hyphae. 3 . Habitat: Found in various environments, including soil, plant debris, and as pathogens. 4 . Diversity: Include many molds and some yeast-like fungi. 5 . Economic Importance: Some species are used in antibiotic production (e.g., Penicillium), while others cause plant and animal diseases (e.g., Fusarium, Aspergillus). 6 . Misclassification: Originally grouped together due to the absence of observed sexual stages, now largely integrated into more accurate classifications based on molecular data. DEUTEROMYCETES

11. The E conomic importance of F ungi 1. Agriculture : Biocontrol : Certain fungi act as natural pesticides by controlling pests and pathogens, reducing the need for chemical pesticides (e.g., Trichoderma). Mycorrhizae : Symbiotic relationships between fungi and plant roots enhance nutrient and water uptake, improving crop yields and soil health. 2. Medicine : Antibiotics : Fungi produce antibiotics like penicillin, which has revolutionized medicine by treating bacterial infections. Immunosuppressants : Compounds like cyclosporine, derived from fungi, are crucial in preventing organ transplant rejection. Antifungals : Fungi are sources of antifungal agents used to treat fungal infections. 3. Food Industry : Fermentation : Yeasts (e.g., Saccharomyces cerevisiae) are essential in baking, brewing, and winemaking. Edible Fungi : Mushrooms (e.g., Agaricus bisporus, shiitake) are cultivated and consumed worldwide for their nutritional value. Enzymes : Fungi produce enzymes used in food processing, such as amylases, proteases, and lipases.

12. 4. Biotechnology: Industrial Enzymes: Fungi produce enzymes used in detergents, paper manufacturing, and biofuel production. Biofactories: Fungi can be engineered to produce pharmaceuticals, biofuels, and other valuable chemicals. 5. Environmental: Decomposition: Fungi play a crucial role in breaking down organic matter, recycling nutrients back into ecosystems. Bioremediation : Certain fungi can degrade environmental pollutants, including petroleum hydrocarbons and heavy metals, helping clean contaminated sites. 6. Pathogens: Plant Diseases: While detrimental, fungi like rusts, smuts, and molds can significantly impact agricultural productivity, prompting the development of better management strategies and crop varieties. Animal and Human Diseases: Some fungi cause diseases, leading to economic costs in healthcare and livestock management, but also driving research and innovation in treatment and prevention.