Zygomycetes

Zygomycetes have what kind of septa?

Aseptate or sparsely septate

What are three genuses of Zygomycetes?

1. Rhizopus

2. Mucor

3. Syncephalastrum

What disease is caused by Rhizopus spp?

Zygomycosis

What are the clinical manifestations of Zygomycosis?

1. Rhinocerebral

2. Pulmonary

3. Disseminated

4. Gastrointestinal

5. Cutaneous

6. Miscellaneous

How is zygomycosis commonly manifested in people with diabetic ketoacidosis?

Rhinocerebral

How is Zygomycosis commonly manifested in people with leukemia?

Pulmonary

What organism is this? Obverse or reverse?

Rhizopus obverse

What is formed on Rhizopus species where the stolon and sporangiophores meet?

Root-like hyphae (rhizoids)

What is formed at the termination of the sporangiophores?

A dark, round sporangium containing a columella with many oval, colorless or brown spores

What organism is this?

Rhizopus

What is the clinical significance of mucor species?

It’s a common contaminant, but can cause zygomycosis

What species is this? Obverse or reverse?

Mucor obverse

What is the shape of the sporangiophores on mucor species?

Long and branched

What do the sporangiophores on mucor species bear?

Terminal round, spore-filled sporangia

Where is the columella in mucor species? How is it seen?

1. Inside the sporangium wall

2. When the sporangium wall ruptures

Does mucor have rhizoids?

No

What species is this?

Mucor (unruptured sporangia)

What species is this?

Mucor with ruptured sporangia

What is the clinical significance of Syncephalastrum?

Contaminant; not known to be pathogenic

What species is this? Obverse or reverse?

Syncephalastrum obverse

What is located on the sporangiophore of Syncephalastrum spp?

Chains of round spores enclosed in finger-like tubular merosporangia

What organism is Syncephalastrum commonly mistaken for?

Aspergillus spp.

How is Syncephalastrum different than Aspergillus?

1. Syncephalastrum has conidia inside merosporangia whereas Aspergillus has them in free chains

2. Syncephalastrum doesn’t have phialides

What species is this?

Syncephalastrum