Fungi may not look all that appealing growing on an old, forgotten about piece of bread in the back of your fridge, but up close, these microscopic organisms can be quite eye-catching and even life-saving; take the Penicillium chrysogenum fungus, which is the source of the first antibiotic Penicillin. In fact, the Kingdom Fungi is filled with a slew of amazing organisms, ranging from benign and beneficial to harmful and lethal.
Above, fungi grow alongside bacteria in an agar plate, which is used to culture and observe microorganisms. [Alien Coffee Mug: Get Yours in the SPACE.com store]
Candida albicansis the most common disease-causing fungus in humans and can be found in most people's bodies, mainly in the mouth and gastrointestinal tract. The fungus, which grows in colonies (like the circular ones shown above), is not harmful if kept in check by our natural gut flora. But overgrowths of the yeast can lead to harmful infections, especially among those with weakened immune systems.
Under a microscope, the fungus Aspergillus niveusresembles a dandelion. This fungus belongs to the Aspergillusgenus, which consists of hundreds of mold species. While most fungi reproduce asexually, in 2005, scientists reported one species of Aspergillus "having sex." [Read full story]
A small sample taken from dirty hands and placed in an agar plate led to the patterned bloom of this dark gray fungus, along with a small bacterial colony on the left.
The above Chaetomium cochliodes fungus looks like a miniature version of a round, spindly sea urchin.
Shades of Green
This magnified view of a fuzzy fungal colony shows bands of various green colors growing in a tree-ring pattern.
The fungus Trichothecium roseum is a plant pathogen that is responsible for many plant diseases. For example, it causes "apple scab," a disease that results in the development of dark lesions on an apple tree's fruit and leaves. T. roseumcan be found in soil and on decaying plant material.
Another magnified image of mold colonies growing in banded, circular patterns on an agar plate. Depending on the species, fungi can be red, pink, orange, yellow, white, green, brown, black and — of course — gray.
In June, researchers at San Francisco State University discovered a mushroom species in the forests of Sarawak, Malaysia, that looks like a bright orange sea sponge and smells vaguely fruity. The researchers named it Spongiforma squarepantsii after SpongeBob SquarePants, because the spore-producing area of the fungus looks like a seafloor carpeted in tube sponges.
To Eat or Not to Eat
White, gray and aqua-tinted fungi can often be found growing on old leftovers. Seeing fungi on your food is a sure sign that it's time to throw it out, but some foods, such as blue cheese, are intended to be eaten with their moldy parts. For example, Camembertand Brie cheeses are made using the fungus Penicillium camemberti, which gives the cheeses their distinctive white outer crusts.
Another shot of various mold species growing in colonies alongside each other within an agar plate. Like other types of fungi, mold can develop anywhere there are sufficient nutrients, warmth and humidity.
Penicillium italicumis another plant pathogen. It grows as a blue mold and loves to feed on citrus fruits — you may have seen it sprouting on spoiled tangerines.
The above microscopic photo shows a sporangium, or structure in which spores form, containing a fungus spore of the genus Rhizopus, fungi that can often be spotted on old bread and fruit.
White and Fluffy
This "snowball scene," shows bacteria, yeast and mold growing in an agar plate. Yeast is a unicellular fungus that can grow on food or human skin because it only requires warm temperatures, moisture and food in the form of starch or simple sugars to multiply.
Root Rot Fungus
The Bipolaris sorokiniana fungus can be found in soil and causes various plant diseases. It is a common source of root rot in wheat crops worldwide.
This microscopic view shows the volcano-like surface of a mold of the Penicillium genus growing on the surface of a decaying lemon.