Friday, November 30, 2012

Fungal Word Friday: Teleomoprh

A Teleomorph is the sexual stage of a fungus.
The teleomorph form of Microsphaera penicillata.

Photo Credit: Ninjatacoshell (Own work) [CC-BY-SA-3.0 ( or GFDL (], via Wikimedia Commons

Friday, November 23, 2012

Fungal Word Friday: Clamp Connection

A cross structure formed by hyphal cells that helps ensure each cell or or septately segmented portion of hypha receives a differeing set of nuclei.

A picture with several Clamp Connections visible.

 For further information the following diagram helps show us the formation process of a clamp connection.

Clamp_formation.jpg (28179 bytes)
Formation of a Clamp Connection

Formation Diagram credit:

Photo Cred:By Alan Rockefeller (Own work) [Public domain], via Wikimedia Commons

Friday, November 16, 2012

Fungal Word Friday: Biseriate

Specialized conidiogenous cells that produce conidia without increasing in length, and arising from metulae as in the genus Aspergillus. The word means "arranged in two rows."
A biseriate conidiophore of Aspergillus alliaceus.

Photo Cred: By Ninjatacoshell (Own work) [CC-BY-SA-3.0 ( or GFDL (], via Wikimedia Commons

Thursday, November 15, 2012

Foreign Spore Germination: Tumblr

Ok, this isn't your normal Spore Generation. Usually I use those to point you to an article that covers mycological news better and faster than I. This Time I am giving you a fun Tumblr aptly called Fungi:


They have some great photos (like the one below), intermixed with news stories, recipes and personal anecdotes. Go give them a look.

Wednesday, November 14, 2012

How Cryptococcus Bypasses the Blood Brain Barrier

ResearchBlogging.orgCordyceps is widely known as the zombie fungus because it likes to take over the brain functions of it victim. Often causing them to do things they normally wouldn't and leading to their demise.

But Cordyceps is not something that humans have to worry about. No, we have our own fungal nasties and one of the worst is Cryptococcus neoformans... I mean it has the word "Crypt" right there in its name! But what does C. neoformans have to do with Cordyceps?

Cryptococcus neoformans
Well, for starters, it infects the brain. In fact it is the causal agent of the most common fungal disease of the central nervous system. Cryptococcal meningoencephalitis is a very dangerous illness, and is actually a major cause of death in AIDS patients.

Our brain does have a good nervous system defense mechanism however; the Blood Brain Barrier. This series of tight junctions along its capillaries separates circulating blood from the nervous systems extracellular fluid. It acts basically as a gateway, restricting the diffusion of foreign particles and larger molecules into the cerebrospinal fluids, while allowing the small needed molecules (Oxygen, Hormones, etc.) through. This generally causes a pretty good barrier... but C. neoformans may have another thing in common with Cordyceps...

A study published in PLOS One finds C. neoformans takes control of the Endothelial cells that constitute the Blood Brain Barrier. Not in the grand way that Cordyceps does, but in a much simpler way. It causes the cell to induce fusogenic activity, and fuses into the very barrier meant to keep it at bay.

Cryptococcus neoformans-Derived Microvesicles Enhance the Pathogenesis of Fungal Brain Infection

You see, while C. neoformans grows and infects, it produces microvesicles which contain components for the fungus's capsule. This capsule is generally considered to be a major determiner of how virulent a strain is because those lacking it are avirulent. These vesicles travel across the cell wall of the fungus carrying the building blocks to bio-synthesize the capsule.

This study demonstrates the potential of these microvesicles in helping the pathogen traverse the blood brain barrier.

To start, the researchers fused a fluorescence protein into one of the most common proteins in C. neoformans derived microvesicles in order to directly view presence and concentration of their formation.

When human endothelial cells, such as those in the blood brain barrier, were exposed to the microvesicles ruffling of the plasma membrane was detected. As time progressed during incubation the fluorescence started increasing in the endothelial cells, suggesting that C. neoformans had invaded and was secreting more microvesicles within the cell.

Looking at density gradients to determine the mechanism for these effects the scientist discovered an uptake of lipid raft activity in the presence of the C. neoformans microvesicles. This means that when these microvesicles are around, the cell itself increases the ability for the invader to adhere to and travel across the membrane barrier.

In addition to this cell inducing, a secondary test to determine whether cell fusion took place was conducted. By dying multiple cell aliquots in distinct colors and presenting portions of them with microvesicles fusion would be detected by multi-fluorescent cells. And just as predicted, those not exposed did not fuse, while those presented with the invader did.

Tests run in vivo with mice demonstrated that by increasing amounts of these microvesicles, along with a C. neoformans infection, there was a significant increase of brain infection by the fungus. Thus the team demonstrated that Cryptococcus neoformans derived microvesicles play a significant role in brain invasion.

In this study, a glimpse of how devious pathogenic fungi  can be is revealed. While the more dramatic members, such as Cordyceps, garner picture worthy attention. The subterfuge practiced by Cryptococcus is just as deadly a form of mind control. More akin to a vampire glamoring you to inviting it in, than to outright controlling your body like a puppet.

A little too "In your face" for Cryptococcus.

Awesome Researchers:
Huang, S., Wu, C., Chang, Y., Kwon-Chung, K., Brown, R., & Jong, A. (2012). Cryptococcus neoformans-Derived Microvesicles Enhance the Pathogenesis of Fungal Brain Infection PLoS ONE, 7 (11) DOI: 10.1371/journal.pone.0048570
Photo Cred: By Dr. Graham Beards (Own work) [CC-BY-SA-3.0 (], via Wikimedia Commons

Friday, November 9, 2012

Fungal Word Friday: Acrosporogenous

In conidial maturation, when the cells deliminate and mature in sequence from base to apex as the conidium expands.
Diagram conidial development.

Photo Source:

Friday, November 2, 2012

Mushroom of the Month: Pear Shaped Puffball

Is it already November? Well I guess it is time to highlight another mushroom. This week we will be running the per shaped puffball, Lycoperdon pyriformes, through an identification key.

Pear Shaped Puffball, Lycoperdon pyriformes

1. The mushroom does not grow on other mushrooms.
2. There are no gills.
3 There are no pores.
4. It lacks teeth or spines.
5. It isn't covered, or at least partially covered, by a foul smelling slime.
6. The mushroom is more or less shaped like a ball, or in this pictures case a ball raised on a stem.
7. The mushroom is smaller than the size of a fist.

This key gets us to the family Lycoperdaceae. For further keying to the species we will turn to a more technical series of identifiers:

1. The Spore case opens by pores or a fissure at the apex.
2. Has various base shapes but not radicating.
3. When mature the fruiting body looses part of its outer layer, but not in a way as to become star-like.
4. The spores inside the mature spore case are loose and powdery and any internal fibers are loose and soft.
5. There is a sterile base and chambered lacunae, with the exoperidium not peeling away from the spore case.
6. And finally, The mushrrom body is growing on wood or wood debris.

These key traits get us to Lycoperdon pyriforme:

1.5 to 3 cm broad; 2 to 3 cm high; pyriform to subglobose; may be plicate at juncture of enlarged portion with stipe-like base. Connected to substrate by numerous white rhizomorphs. Pallid to tawny brown immature, darker rusty brown at maturity -- some yellowish; areolate patches darker. Exo breaking into areolate patches that divide into smaller units, which on drying form minute granules. At times exo over apex consists of small spines and granules. Remains of exo relatively persistent and rough to touch. Apical pore slow to form, often irregular. Sterile base slight to prominent depending on shape. On wood or sawdust on ground, cespitose to scattered, September to heavy frost. Old cases persist to next summer.
 For more information here is the Wikipedia entry on this edible puffball:

Lycoperdon Pyriforme

Fungal Word Friday: Zygospore

A zygospore is thick-walled sexual spore formed by the fusion of two similar gametangia. It is, as the name suggests, characteristic of the Zygomycetes.
The zygospore stage of Rhizopus stolonifer.

Photo Cred: Course materials for BOT135 taught at University of Hawaii by George Wong.