LESSON 8 (Characteristics and Classifications of Fungi)

Glucan

The most abundant polysaccharides in the cell walls of fungi

Chitin

A polymer of N-acetylglucosamine commonly found in the cell walls of fungi.

Mycelium

The mass of branched, tubular filaments of fungi

Hypha

The branching filaments that make up the mycelium of a fungus

Septum

The internal walls separating the cells of a fungus.

Thallus

A plantlike vegetative that lacks differentiation into distinct parts and does not grow from an apical point.

Imperfect fungi

species that **do not display** a **sexual phase**

commonly known as **mold**

Deuteromycota

**former phylum grouping** of imperfect fungi

Candida albicans

Some Clinically Relevant Fungi:

**Opportunistic fungal** pathogen causing **candidiasis** in humans

Occurs in **immunocompromised** people

Emericella spp.

Some Clinically Relevant Fungi:

Common in **tropical** and **subtropical region**

Capable of **causing** **allergenic** and **asthmatic** reactions in sensitive individuals

Blastomyces dermatitis

Some Clinically Relevant Fungi:

Causative agent of **blastomycosis**

Disease predominantly **endemic** in **North America.**

Naturally **lives** in **soi**l and **organic materials**

Cryptococcus neoformans

Some Clinically Relevant Fungi:

Causative agent of **cryptococcosis**

Affects **immunocompromised** **patients**

**Acquired** through **inhalation** of yeast cells

Coccidioides spp.

Some Clinically Relevant Fungi:

Causative agent of **coccidioidomycosis**

Affects **immunocompromised** individuals, persons with commorbidities, and pregnant women

Histoplasma spp.

Some Clinically Relevant Fungi:

Causative agent of **histoplasmosis**

**Lives** in **soil** containing large amounts of **bird** or **bat** **droppings**

**Acquired** after **breathing** in the **spores** from the air

Pneumocystis jirovecii

Some Clinically Relevant Fungi:

Causative agent of **Pneumocystispneumonia** (PCP)

**Used** to be **classified** as a **protozoan**

Spores, Teleomorphs & Anamorphs, Sexual & Asexual Reproduction, Pheromones

Ways Fungi reproduce

Chytridiomycota

Five true phyla of Fungi:

**simplest** and **most** **primitive** true fungi

most are **unicellular**

Ecological **habitat** and cell **structure** have much in common with **protists**

Zygomycota

Five true phyla of Fungi:

Most species are **saprobes** (act as decomposers)

Performs **sexual** and **asexual** **reproduction**.

Basidiomycota

Five true phyla of Fungi:

**Club** **fungi**

Fruiting bodies are termed **fairy** **ring**.

Shelf fungus, smuts and rusts; toadstools, and shelf fungi

Ascomycota

Five true phyla of Fungi:

Formation of ascus (sack-like structure)

Yeasts for **baking**, **brewing**, and **winemaking**

**Fermentation** of rice to produce sake

**Plant** **pathogens**

**Opportunistic** human pathogens

Glomeromycota

Five true phyla of Fungi:

Closely **associated** with the **root** of **trees**.

Arbuscular mycorrhizae

Does **not produce sexually** and **do not survive** without the **presence** of **plant** **roots**.

Pharmacology, Neuroscience, Nutrition and Dietetics

Mycology is important to these allied sciences

300

Number of species known to cause human infections

Fungi

Non-phototrophic and nonvascular eukaryotic organisms containing rigid cell walls

key features of fungi

chitinious cell walls, plasma membranes containing ergosterol, 80S rRNA, and microtubules composed of tubulin.

mycology

branch of natural science dealing with the study of fungi.

CHYTRIDIOMYCOTA, ZYGOMYCOTA, BASIDIOMYCOTA, ASCOMYCOTA, and GLOMEROMYCOTA

WHAT ARE THE FIVE TRUE PHYLA OF FUNGI?

Imperfect fungi

are species that do not display a sexual phase