Showing posts with label fungus. Show all posts
Showing posts with label fungus. Show all posts

Saturday, 4 January 2014

Okay, Why so much Fungus???



This blog is called ‘Fun With Microbiology’, not’ Fun With Mycology’ – so what gives?  Why the disproportionate number of Fungal posts?

Well, this blog came about primarily because, after my injury, I needed some way to fill my time after regular work hours while waiting for my ride home.  With my return to work, I discovered that the laboratory had acquired some new “Toys” for photographing interesting microbiological specimens.  Surprisingly, few were interested in utilizing them, whereas with my previous interest in photography, I was only too happy to take command of these tools.

This blog is primarily about photography - about describing microbiology through pictures.  It is also about “interesting” cases – some of the less commonly encountered observations usually not described in text books.   (eg Mycobacteria in a gram stain, Strongyloides  tracks on agar plates, VDE –bacteria that need  antibiotics to survive.) Finally, it is about sharing my photographs with anyone who may find them of interest.

So, why so much fungus?  Well, bacteria exhibit a limited number morphological variations, as I’ve attempted to illustrate (right).  Generally speaking, an E.coli cell looks pretty much like a Salmonella cell, looks like a Citrobacter cell.  While important, yet often subtle, differences in morphology do occur in bacteria, I have chosen not to pursue them on this site.  Bacteria will be documented when the topic best lends itself to photographic interpretation.  

 Generally speaking, there are a limited number of bacterial morphotypes to explore with photography.

While I wish to pursue Parasitology a bit more extensively, I find myself limited to what cases present themselves in our acute care community hospital.

Numerous fine textbooks on Clinical Mycology are in print (see sidebar); however I have frequently found that the description ‘in text’ relates poorly to the one or two small supporting photographs offered.  Fungi are three dimensional organisms whose structure varies as they mature.  I’ve attempted to document these fascinating organisms from all angles and in all pertinent stages of development.

In summary, whether saprophytic contaminants or clinically significant isolates. fungi are the most photogenic microbiological organisms and present themselves in sufficient numbers to keep this blog going.

Finally, I offer my apologies for the rather lame name of this Blog.  My wife suggested I explore ‘blogging’ as a way to pass the time while bed bound, recovering from a catastrophic injury.  I jokingly chose this name never thinking I’d develop it past the few print photos I had taken years earlier.  Too late to change it now…

Saturday, 19 May 2012

Sphaerita spp.


Sphaerita spp.

“Big bugs have little bugs, on their backs to bit them’
Little bugs have lesser bugs, and so on ad infinitum”
Anonymous

Some protozoan parasites can themselves be parasitized.  A hyper-parasite! The genus Sphaerita is considered to be a lower fungus and some species are capable of invading the cytoplasm of some amoeboid parasites.  Another parasite of parasites is Nucleophaga species which invades the nucleus.  Sphaerita, (sometimes called Polyphaga spp.) appear as tightly packed clusters within the cytoplasm and measure approximately 0.5 µm to 1.0 µm.

The parasite show below is possibly an Entamoeba coli, however the nucleus is not visible as it is out of the plane of focus.  Sphaerita appears as the small dots within the cytoplasm.

 An amoeboid parasite itself parasitized by the fungal parasite Sphaerita spp.  The Sphaerita appear as the neatly arranged circular dots withing the cytoplasm.
 Iron hematoxylin stain (X1000) Nikon


 An amoeboid parasite itself parasitized by the fungal parasite Sphaerita spp.  Doesn't appear to be digested material or inclusions. This parasite appears to have a rather dark blotchy karyosome reminiscent of Iodamoeba  bütchlii.  Unfortunately I failed to record measurements when I took these photos.  E.coli, Iodamoeba  bütchlii and E.nana were all present in this particular specimen.
Iron hematoxylin stain (X1000) Nikon

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Thursday, 17 May 2012

Microsporum gypseum


Microsporum gypseum (Fungus/dermatophyte)

Ecology & Pathology: Micrsporum gypseum is a geophilic (soil loving) dermatophyte which occasionally causes skin infections (tinea corporis) and/or scalp infections (tinea capitis). Onychomycosis (nail infections) have also been reported.  It has also been isolated from horses, dogs, cats and rodents.  A cosmopolitan fungus (found worldwide).

Macroscopic Morphology:  As with other fungi, colour is influenced by the media it is grown on.  Colony generally described as yellowish-buff to a dark cream or tan colour in colour.  The colony may develop a sterile white ‘feathered’ hyphal border or a cottony white raised center.  The reverse may be yellow, orange-tan or brownish-red in colour with possible pink to purplish tinges.  Colonies are generally flat with a granular or powdery texture and exhibit a moderately rapid growth rate, maturing in about one week.

Microsporum gypseum SAB at 7 Days (Nikon)

Microscopic Morphology:  M.gypseum has septate hyphae along which sessile or stalked clavate (club shaped) microconidia (3 – 8 µm X 2 -3 µm) may be found.  The fusiform (spindle shaped) macroconidia (8 – 15 µm X 22 – 60 µm) are relatively thin walled, verrucose (with bumpy surface) and contain about 3 – 6 internal cells.  M. gypseum’s macroconidia has a rounded apical end while the base is truncated and may show an annular frill.  They are usually produced in great numbers.  This differentiates M.gypseum’s macroconidia from the M.canis macroconidia which has rather pointed ends and the rather rare & distorted macroconidia produced by M.audounii.

Note: Photos that follow were taken with the Leica DMD-108 digital microscope.

 M.gypseum -Slide culture at 48 hours (X100 LPCB)

 M.gypseum -Slide culture (X250 LPCB)
Hyphae throughout, some showing microconidia, larger macroconidia at left of photo

M.gypseum -microconidia along hyphae are more visible in this photo. Several macroconida throughout. (X250 LPCB)

M.gypseum - another view of both macro & micro conidia (X250 LPCB)

M.gypseum macroconidia (X 400 LPCB)
(Note 100 µm bar at top right of photo)

M.gypseum macroconidia and sessile microconidia attached to hyphae
(X400 LPCB)

M.gypseum clavate microconidia (sessile & stalked?) attached to hyphae
(X1000 LPCB)

M.gypseum - numerous fusiform (spindle) shaped macroconida
(X400 LPCB)

M.gypseum - numerous macroconidia showing up to six internal cells in each.  Rough 'verrucose' surface is evident.  Adhesive tape preparation. (X1000 LPCB)

M.gypseum macroconidia - on left still attached to conidophore,  Rough verrucose surface on lower middle macroconida. (X1000 LPCB)

M.gypseum - more of the same, but I just love them!
(X1000 LPCB)

M.gypsium - macroconidia and a few microconidia (X1000 LPCB)

M.gypseum macroconidium showing rounded apical end and truncated end where once attached to conidiophore.  Six internal cells or compartments visible.  Rather thin walled with somewhat rough texture evident.  (X1000+10 LPCB)

M. gypseum - nearly identical to the macroconidia above, this cell also has six internal cells or compartments with verrucose surface.  Nature's own canoe!  (X1000+10 LPCB)
*  *  *
  Physiological Tests:  M.gypseum is positive for the hair perforation test.  It requires no special growth factors and produces no change in pH when inoculated into BCP-milk solids-glucose media.  It is urea positive.

 M.gypseum - Intended as computer wallpaper (1024 X 768 when posted)