Micrasterias is a Desmid - a group of green algae mostly found in neutral to acidic fresh waters and sphagnum bogs. Most are unicellular, though a few form chain-like colonies. Each cell is constructed of 2 semicells which are mirror images of each other. In Micrasterias the cells are flattened ... Read More
Nitrate reduction test for the reduction of nitrate in nitrate media, to determine if the bacteria contains nitrate and/or nitrite reductase. Organism were incubated for 48 hr's at 37 degree's in nitrate media then reagents added.
Nitrate broths after the addition of 10 drops re... Read More
Gram-positive cocci showing various morphological arrangements including diplococcus and tetrads. (approx. X970). Taken from the Wistreich Collection, appearing exclusively on MicrobeWorld. Read More
This photomicrograph is showing Neisseria gonorrhoeae in a cervical smear using the Gram-stain technique. Thanks to the CDC's PHIL for the image. Read More
This color-enhanced photomicrograph shows different species of bacteria that cause dental plaque - a colorless film that forms on teeth caused by the growth of bacterial colonies. Plaque develops naturally, and in most cases can be easily removed with regular brushing. However, if left it can ha... Read More
Under a magnification of 200x, and using a lactophenol cotton blue mount fixation technique, this photomicrograph reveals some of the ultrastructural morphology exhibited by a Mucor sp. fungal organism. This image depicts two sporangia, a mature structure, which had ruptured, releasing its conte... Read More
Magnified 1000X, this Liefson’s flagella stained photomicrograph revealed the presence of a number of flagellated Brevundimonas diminuta, formerly known as Pseudomonas diminuta.
After having run DNA-rRNA hybridization studies, the genus Brevundimonas has been reclassified as a member of the p... Read More
Histoplasma capsulatum in intestinal villi of brown house bat. Eptesicus fuscus from house near Clarksburg, MD. GMS stain Read More
Large (about 5 mm in diameter), lactose positive colonies of Klebsiella pneumoniae on desoxycholate-citrate agar. Cultivation 37°C, 24 hours.
Klebsiella pneumoniae is a common source of hospital-acquired infections. Some of the strains can carry plasmids that harbour genes conferring resistan... Read More
Marburg hemorrhagic fever (Marburg HF) is a rare, severe type of hemorrhagic fever which affects both humans and non-human primates. Caused by a genetically unique zoonotic (that is, animal-borne) RNA virus of the filovirus family, its recognition led to the creation of this virus family. The fi... Read More
Corynebacterium diphtheriae. Elek plates showing lines of identity. Paper strip is saturated with antitoxin organisms (black growth) producing toxin Read More
Basidiobolus haptosporus. One subspherical spore which has been produced by replication and one adhesive spore produced by replication Read More
The presence of a pellicle on the surface of a broth medium. Taken from the Wistreich Collection, appearing exclusively on MicrobeWorld. Read More
This scanning electron micrograph (SEM) depicts a number of Leptospira sp. bacteria atop a 0.1. µm polycarbonate filter.
Leptospira interrogans causes leptospirosis, a usually mild febrile illness that may result in liver or kidney failure. Leptospira is a flexible, spiral-shaped, Gram-negati... Read More
Colonies of Histoplasma capsulatum growning on blood agar plates. Incubated at 30C. Note glabrous colonies without aerial mycelium Read More
A pink-pigmented strain of Pseudomonas aeruginosa is shown in the picture. This was photographed in University of Colorado Hospital's clinical lab by the microbiology department. The organism is shown on Mueller-Hinton agar for Kirby-Bauer sensitivity testing.
The pigment pyorubin is responsi... Read More
Magnified 1125X, this Gomori-stained photomicrograph revealed the presence of a Penicillium marneffei yeast cell, which was found in a specimen of human spleen.
P. marneffei is endemic to Southeast Asia, where it is one of the more common HIV-related opportunistic infections. Penicillium spp.... Read More
As referenced in the most recent episode of This Week in Parasitism, Dickson Despommier, Mailman School of Public Health, Columbia University, and Yuzo Takahashi, Department of Parasitology, Gifu University School of Medicine, have posted hundreds of scanning electron microgra... Read More