Gram-Negative Bacteria

Etiologic Agents of Ehrlichioses

E. coli O157:H7 (chronology)

Scanning electron micrograph of Leptospira

Scanning Electron Micrograph of Acinetobacter anitratus

Transmission electron micrograph of Escherichia coli O157:H7

Scanning Electron Micrograph of Acinetobacter anitratus

Scanning Electron Micrograph of Pseudomonas aeruginosa

Scanning electron micrograph of Bordetella bronchiseptica

Scanning Electron Micrograph of Burkholderia cepacia

Scanning Electron Micrograph of Citrobacter freundii

Scanning Electron Micrograph of Providencia alcalifaciens

Histopathology of spleen in fatal human plague

Histopathology of lymph node in fatal human plague.

Histopathology of lung in fatal human plague.

Blood agar plate culture of Brucella suis.

Blood agar plate culture of Cardiobacterium hominis.

Blood agar plate culture of Campylobacter fetus s. intestinalis.

Blood agar plate culture of Chromobacterium violaceum.

Histopathology showing Borrelia burgdorferi spirochetes in Lyme disease. Dieterle silver stain.

Histopathology showing Treponema pallidum spirochetes. Modified Steiner silver stain.

Histopathology of leptospirosis, kidney.

Rickettsia tsutsugamushi budding from mouse peritoneal mesothelial cell.

Phagocytosis of Rickettsia tsutsugamushi by mouse peritoneal mesothelial cell.

Rickettsia tsutsugamushi within intact phagocytic vacuole of mouse peritoneal mesothelial cell.

Rickettsia tsutsugamushi within the remains of a phagocytic vacuole of mouse peritoneal mesothelial cell.

Rickettsia tsutsugamushi dividing within the cytoplasm of a mouse peritoneal mesothelial cell.

Multiple Rickettsia tsutsugamushi free within the cytoplasm of a mouse peritoneal mesothelial cell.

Multiple Rickettsia tsutsugamushi free within the cytoplasm of a mouse brain capillary endothelial cell.

Single Rickettsia tsutsugamushi free within the cytoplasm of a mouse brain capillary endothelial cell.

Thrombus due to infection with Rickettsia tsutsugamushi, mouse brain capillary.

Legionella pneumophila multiplying inside a cultured human lung fibroblast.

Escherichia coli in spinal fluid. FA stain (digitally colorized).

Neisseria meningitidis, group C, in spinal fluid. Penicillin-treated.

Neisseria meningitidis, group C, in spinal fluid.

Pseudomonas mendocina. Leifson flagella stain (digitally colorized).

Pseudomonas pseudoalcaligenes. Leifson flagella stain (digitally colorized).

Pseudomonas maltophila. Leifson flagella stain (digitally colorized).

Vibrio cholerae. Leifson flagella stain (digitally colorized).

Campylobacter fetus. Leifson flagella stain (digitally colorized).

Bordetella bronchiseptica. Leifson flagella stain (digitally colorized).

Alcaligenes faecalis. Leifson flagella stain (digitally colorized).

Alcaligenes dentrificans. Leifson flagella stain (digitally colorized).

Aeromonas shigelloides. Leifson flagella stain (digitally colorized).

Aeromonas hydrophila. Leifson flagella stain (digitally colorized).

Pseudomonas diminuta. Leifson flagella stain (digitally colorized).

Proteus mirabilis. Dienes's reaction.

Haemophilus influenzae satelliting around Staphylococcus aureus.

Alcaligenes odorans. Gram stain.

Stab culture of Legionella pneumophila.

Transmission electron micrograph of Legionella pneumophila.

Positive indirect FA test for Legionella pneumophila.

Positive FA test for Neisseria gonorrhoeae.

Stab cultures of Salmonella typhi and controls.

Scanning electron micrograph of Leptospira interrogans strain RGA.

Treponema pallidum, darkfield preparation.

Alcaligenes faecalis. Flagella stain.

Alcaligenes faecalis. Gram stain.

Alcaligenes denitrificans. Flagella stain.

Alcaligenes denitrificans. Gram stain.

Agrobacterium radiobacter. Gram stain.

Aeromonas hydrophila. Gram stain.

Actinobacillus suis. Gram stain.

Actinobacillus lignieresi. Gram stain.

Acinetobacter calcoaceticus. Gram stain.

This photomicrograph depicts the Gram-negative bacterium Acinetobacter calcoaceticus using the Gram-stain technique.

Achromobacter xylosoxidans. Gram stain.

Leptospira bacteria in liver impression smear. FA stain.

Bartonella vinsonii subsp. berkhoffii seroprevalence in 869 California coyotes (1994-1998).

Bar graph showing rate of reptile-associated Salmonella serotypes isolated from humans.

Blood agar plate culture of Eikenella corrodens.

Blood agar plate culture of Flavobacterium meningosepticum.

Blood agar plate culture of Flavobacterium odoratum.

Blood agar plate culture of Haemophilus aegyptius.

Blood agar plate culture of Haemophilus aphrophilus.

Blood agar plate culture of Haemophilus influenzae.

Blood agar plate culture of Haemophilus parahaemolyticus.

Leptospira bacteria, FA stain of liver impression smear.

Brucella species are gram-negative in their staining morphology.

Brucella melitensis colonies.

Francisella tularensis is gram-negative in its staining morphology.

Francisella tularensis as seen with Direct Fluorescent Antibody Stain (DFA), 1000x magnification.

Francisella tularensis as seen with Direct Fluorescent Antibody Stain (DFA).

Francisella tularensis, Colonization on Cysteine Heart Agar after 72 hours.

Francisella tularensis, Colonies grown on Chocolate Agar, 72 hours.

Yersinia pestis, Gram-negative bacillus, 1000x Magnification.

Yersinia pestis, Gram-negative bacillus.

Yersinia pestis, Gram-negative bacillus, 1000x Magnification.

Yersinia pestis, Direct Fluorescent Antibody Stain (DFA), 40x Magnification.

Yersinia pestis, Direct Fluorescent Antibody Stain (DFA), 200x Magnification.

Yersinia pestis, Direct Fluorescent Antibody Stain (DFA), 100x Magnification.

Yersinia pestis on Sheep Blood Agar, 72hrs.

Burkholderia pseudomallei grown on sheep blood agar for 24 hours.

Burkholderia pseudomallei grown on sheep blood agar for 48 hours.

Burkholderia pseudomallei grown on sheep blood agar for 72 hours.

Burkholderia pseudomallei grown on sheep blood agar for 96 hours.

Brucella melitensis Gram-stain.

Vibrio cholerae causing increased mucous production seen in this intestinal biopsy.

Adult cholera patient with "Washer Woman's Hand" sign.

Typical Vibrio cholera contaminated water supply.

Photomicrograph of Haemophilus influenzae using immunofluorescence.

Photomicrograph of Haemophilus influenzae as seen using a Gram stain technique.

Neisseria gonorrhoeae found in a male with urethritis.

Seen here are small hemorrhages on the skin of a plague victim.

An anteroposterior chest x-ray of a plague patient

Photomicrograph of lung tissue revealing Yersinia pestis organisms.

Right hand of a plague patient displaying acral gangrene.

Salmonella bacteria in tetrathionate enrichment broth stained using direct FA staining technique.

A lab technician taking a photomicrograph during a plague study, 1965.

Mortars and pestles used in plague studies, 1965.

Fluorescent antibody stain of Yersinia pestis.

A man setting traps for rats during a plague study.

Here technologists are carrying out Plague Studies in San Francisco, 1961.

Here a technologist is carrying out Plague Studies in San Francisco, 1961.

A Tularemia lesion on the dorsal skin of the right hand, caused by the bacterium Francisella tularensis.

Flea and Tick Powder for use on domesticated pets will help control flea populations.

Permethrin-treated cotton is collected by rodents and brought back to their nests.

Plague infected male Xenopsylla cheopis 28 days after feeding on an inoculated mouse.

A photomicrograph of Neisseria gonorrhoeae viewed using a Gram-stain technique.

A photomicrograph of Escherichia coli, (Bacillus coli), bacteria using Gram stain technique.

A photomicrograph of Salmonella typhosus bacteria using a Gram stain technique.

A photomicrograph of Salmonella typhosus bacteria using a Flagellar stain technique.

A photomicrograph of the bacterium Brucella melitensis, initially named Micrococcus melitensis.

Photomicrograph of Yersinia (Pasteurella) pestis, sometimes referred to as (Bacillus pestis).

A photomicrograph of Pseudomonas aeruginosa, also known as Bacillus pyocyaneus, bacteria.

A photomicrograph of Haemophilus ducreyi bacteria stained using Gentian Violet.

A Gram-stained urethral exudate from a male patient with urethritis; note the Gram-negative pleomorphic extracellular organisms.

A urethral exudate from a male patient with urethritis; note the presence of Gram-negative N. gonorrhoeae organisms.

Electron micrograph of Neisseria gonorrhoeae bacteria, the causative agent of gonorrhea; magnification 100,000X.

An electron photomicrograph of two spiral-shaped Treponema pallidum bacteria.

Photomicrograph of Borrelia burgdorferi, the bacterium that cause Lyme disease.

Salmonella bacteria in tetrathionate enrichment broth stained using direct FA staining technique.

Photomicrograph of liver tissue revealing the presence of Leptospira bacteria.

Photomicrograph of kidney tissue, using a silver staining technique, revealing the presence of Leptospira bacteria.

A photomicrograph of a liver smear, using a silver staining technique, taken from a patient with a fatal case of Leptospirosis.

Photomicrograph of kidney tissue, using a silver staining technique, revealing the presence of Leptospira bacteria.

Note the skin rash on this patient�s torso with septicemia due to the systemic spread of Gram-negative bacteria.

This photomicrograph reveals the bacterium Bacteroides thetaiotaomicron grown on blood agar for 48 hours.

This photomicrograph shows the bacterium Fusobacterium nucleatum cultured in a thioglycollate medium for 48 hours.

This photomicrograph shows Bacteroides trichoides after being cultured in a thioglycollate medium for 48 hours.

This photomicrograph shows the bacterium Fusobacterium russii cultured in a thioglycollate medium for 48 hours.

This photomicrograph shows Fusobacterium necrophorum bacteria cultured in a thioglycollate medium for 48 hours.

This photomicrograph shows Fusobacterium mortiferum after being cultured in a thioglycollate medium for 48 hours.

This photomicrograph shows the bacterium Bacteroides biacutus cultured in a thioglycollate medium for 48 hours.

This photomicrograph shows Fusobacterium necrogenes after being cultured in a thioglycollate medium for 48 hours.

This photomicrograph shows Bacteroides vulgatus after being cultured in a thioglycollate medium for 48 hours.

This photomicrograph shows Bacteroides hypermegas after being cultured in a thioglycollate medium for 48 hours.

This photomicrograph shows the bacterium Bacteroides ovatus cultured in a thioglycollate medium for 48 hours.

This photomicrograph shows Bacteroides distasonis cultured in a thioglycollate medium for 48 hours.

This photomicrograph shows Bacteroides fragilis after being cultured in a thioglycollate medium for 48 hours.

This photomicrograph shows Fusobacterium novum after being cultured in a thioglycollate medium for 48 hours.

This photomicrograph shows Bacteroides fragilis after being cultured in a thioglycollate medium for 48 hours.

This photomicrograph shows Fusobacterium nucleatum after being cultured in a thioglycollate medium for 48 hours.

This is a photomicrograph of Fusobacterium nucleatum cultured on blood agar for 48 hours.

This is a photomicrograph of Fusobacterium russii cultured in a thioglycollate medium for 48 hours.

This is a photomicrograph of Neisseria gonorrhoeae the presence of mixed bacterial flora. Note the necrotic neutrophil.

This photomicrograph depicts Neisseria gonorrhoeae bacteria within a neutrophil.

This is a plate culture of Neisseria gonorrhoeae stained with oxidase reagent after 40 hours of incubation.

This is a photomicrograph of Francisella tularensis bacteria using a methylene blue stain.

This micrograph depicts Bacteroides fragilis grown in Schaedler�s broth using gram-stain.

This photomicrograph shows gram-negative Pasteurella ureae bacteria grown in a culture medium for 24 hours.

This is a XLD agar plate culture of Enterobacter sakazakii after 24 hours of growth at 36� C.

This is a sheep blood agar plate culture of Enterobacter sakazakii after 24 hours of growth at 36� C.

This is a MacConkey agar plate culture of Enterobacter sakazakii after 24 hours of growth at 36� C.

This is a SS agar plate culture of Enterobacter sakazakii after 24 hours of growth at 36� C.

This is a trypticase soy agar plate culture of Enterobacter sakazakii after three days of growth at 25� C.

This is a plate culture of Enterobacter sakazakii performed during an antibiogram study.

This antibiogram compares E. sakazakii sensitivity (top) to E. cloacae (bottom) to cephalothin and ampicillin.

This trypticase soy agar plate culture of E. sakazakii is showing mucoid flat colonies after three days growth at 25� C.

This is a trypticase soy agar plate culture of E. sakazakii showing mucoid flat colonies after three days at 25� C.

This is a trypticase soy agar plate culture of E. sakazakii showing wrinkled colonies after three days at 25� C.

These are plate cultures of Enterobacter sakazakii (right) and E. cloacae (left) during a DNAase reaction.

This micrograph depicts the gram-negative bacterium, Fusobacterium fusiforme cultured in blood agar for 48 hours.

This micrograph depicts Bacteroides fragilis ss. fragilis bacteria cultured in blood agar medium for 48 hours.

This micrograph depicts Bacteroides fragilis ss. distasonis bacteria cultured in blood agar medium for 48 hours.

This micrograph depicts Bacteroides fragilis ss. ovatus bacteria cultured in blood agar medium for 48 hours.

This micrograph depicts the gram-negative bacterium Eikenella corrodens.

This micrograph depicts gram-negative Veillonella spp. bacteria.

This micrograph depicts Bacteroides fragilis ss. vulgatus bacteria cultured in blood agar medium for 48 hours.

This micrograph depicts Bacteroides hypermegas bacteria cultured in blood agar medium for 48 hours.

This micrograph depicts Bacteroides fragilis ss. fragilis bacteria cultured in blood agar medium for 48 hours.

This micrograph depicts Bacteroides biacutis bacteria cultured in blood agar medium for 48 hours.

This micrograph depicts the gram-negative bacterium, Fusobacterium novum cultured in blood agar for 48 hours.

This micrograph depicts Bacteroides trichoides bacteria cultured in blood agar medium for 48 hours.

This micrograph depicts Bacteroides clostridiformis bacteria cultured in blood agar medium for 48 hours.

This micrograph depicts the gram-negative bacterium, Fusobacterium mortiferum cultured in blood agar for 48 hours.

This micrograph depicts the gram-negative bacterium, Fusobacterium necrophorum cultured in blood agar for 48 hours.

This micrograph depicts the gram-negative bacterium, Fusobacterium necrogenes cultured in blood agar for 48 hours.

This is a phase-contrast photomicrographic image of Fusobacterium necrophorum.

This micrograph depicts Yersinia pestis bacteria using Direct Fluorescent Antibody Stain (DFA); Magnified 98x.

This is a heart infusion agar culture growing colonies of Yersinia pestis bacteria.

This blood agar culture plate is growing colonies of Yersinia pestis microorganisms at 48 hours.

This is a micrograph of a blood smear containing Yersinia pestis plague bacteria.

This micrograph depicts Pasteurella multocida, using a Gram-stain technique; Magnification: 1125X.

This photomicrograph reveals bacteria adhering to vaginal epithelial cells known as �clue cells�.

This photomicrograph depicts the gram negative bacteria Neisseria gonorrhoeae.

This is an enlargement of a Type-1 colony of Neisseria gonorrhoeae bacteria.

This is a photomicrograph of a rectal smear revealing Neisseria gonorrhoeae, using the Gram-stain technique.

This Gram-stained specimen reveals N. gonorrhoeae intracellular diplococci, leading to a positive diagnosis of gonorrhea.

Here F. mortiferum and C. perfringens grew on PEA agar with inhibition of E. coli and P. vulgaris.

E. coli, F. mortiferum, P. vulgaris, and C. perfringens were grown on a 24hr blood agar culture.

F. mortiferum and C. perfringens, with E. coli and P. vulgaris inhibited, grown on 48hr PEA agar.

This MacConkey plate grew colonies of E. coli, F. mortiferum, P. vulgaris, but not C. perfringens.

This photomicrograph reveals �Donovan bodies� in a skin sample used to diagnose granuloma inguinale.

This photomicrograph depicts Francisella tularensis bacteria as seen with a fluorescent antibody stain.

These are colonies of Escherichia coli bacteria growing on blood agar culture medium.

Note the zone of inhibition around this antibiotic-impregnated paper disk during an antibiotic sensitivity test.

This is an example of an antibiotic sensitivity test on a mixed culture of E. coli and a Proteus sp., at a pH 7.2.

This diagnostic kit is used in clinical bacteriology to test for Salmonella spp. and Proteus spp. infections.

This image shows a diagnostic procedure testing for the presence of the bacterium Vibrio cholerae, the cause of cholera.

This gelatin agar medium was used in the identification of the bacteria Vibrio cholerae, the causal agent of cholera.

This was a of chick RBC test on a slide used in the diagnosis of cholera.

This was a classic sensitivity test for Vibrio cholerae involving Group IV bacteriophage and Polymyxin B.

These Campylobacter fetus (C. fetus ss. jejuni) cultures were grown on Skirrow's and Butzler's medium.

This Campylobacter fetus (C. fetus ss. jejuni) culture was grown on Skirrow's and Butzler's medium.

These are test tubes containing aspirated fleas as part of the San Francisco plague series.

This photomicrograph reveals the histopathology in an acute case of gonococcal urethritis using Gram-stain technique.

This illustration depicts a Gram-stain of a urethral exudate that is diagnostic of gonococcal urethritis.

This photomicrograph depicts the histopathologic changes in splenic tissue in a case of fatal human plague; Mag. 400X.

This photomicrograph depicts the histopathologic changes in lung tissue in a case of fatal human plague pneumonia; Mag. 160X.

This anteroposterior x-ray reveals the resolution of a plague infection with clearing in bilateral lung fields.

This photomicrograph depicts Yersinia pestis bacteria using a fluorescent antibody stain.

This unstained micrograph represents a reactive control VDRL Slide Test; Mag. 100X.

These were two differently concentrated sputum specimen cultures of Histoplasma capsulatum.

This image shows a BHI (Brain Heart Infusion) agar culture growing Leptotrichia buccalis bacteria on day 3.

Note the histopathologic changes in a case of botryomycosis due to Pseudomonas aeruginosa using a Brown-Brenn stain.

This is a micrograph of an exudate taken from a subdural empyema due to an infection caused by multiple genera of bacteria.

This culture dish grew E. coli, F. mortiferum, P. vulgaris, and C. perfringens bacterial colonies.

This photomicrograph reveals �Donovan bodies� in a skin sample used to diagnose granuloma inguinale.

This direct smear microscopic exam revealed the presence of Haemophilus ducreyi indicative of a chancroid infection.

This electron micrograph, viewed at a low magnification depicts the irregularities in the surface of a biofilm culture material.

This SEM reveals irregularities in the surface of a PC (polycarbonate) biofilm coupon that is growing an E.coli biofilm.

This SEM depicts an E. coli (ATCC 11775) biofilm grown on PC (polycarbonate) material using a CDC biofilm reactor.

This SEM depicts an E. coli (ATCC 11775) biofilm grown on PC (polycarbonate) coupons using a CDC biofilm reactor.

This low-mag SEM depicts an E. coli (ATCC 11775) biofilm on PC (polycarbonate) coupons using a CDC biofilm reactor.

This SEM depicts an E. coli (ATCC 11775) biofilm grown on PC (polycarbonate) coupons using a CDC biofilm reactor.

This low-mag SEM shows surface irregularities in biofilm culture material (polycarbonate) growing P. mirabilis bacteria.

This low-mag SEM reveals surface irregularities in a biofilm coupon growing a 24hr biofilm of P. mirabilis (ATCC 29906).

This SEM depicts a P. mirabilis (ATCC 29906) biofilm growing on PC (polycarbonate) coupons using a CDC biofilm reactor.

This agar petri dish culture is growing ampicillin-resistant E. coli and Proteus sp. bacterial colonies.

Here, S. typhi, E. coli, and Proteus sp. bacteria are cultured on bismuth sulfite agar; 48hrs incubation.

Here, S. typhi, E. coli, and Proteus sp. bacteria are cultured on four different culture media.

Thayer-Martin medium is used when transporting or isolating N. gonorrhoeae and N. meningitides bacteria.

This Gram-stain depicts flagellated Vibrio comma bacteria, a strain of V. cholerae; the cause of Asiatic cholera.

This image shows a positive fluorescent antibody tests for the Gram-negative bacterium Neisseria Gonorrhoeae.

This poorly colorized Gram-stain image of a urethral discharge specimen reveals the presence of N. gonorrhoeae bacteria.

Examination of this urethral discharge for Neisseria gonorrhea revealed Gram-negative intracellular rods, NOT diplococci.

This is an enlarged view of a T4, laboratory-grown Neisseria gonorrhoeae bacterial colony.

This photomicrograph reveals the presence of the Gram-negative diplococcus, Neisseria gonorrhea.

This photomicrograph reveals the presence of the Gram-negative bacteria, Neisseria subflava.

This is an enlarged view of a T3, laboratory-grown Neisseria gonorrhoeae bacterial colony.

This is a photomicrograph of a Neisseria gonorrhea specimen treated with a flazo orange fluorochrome counterstain.

This is a photomicrograph of a urethral discharge specimen showing the Gram-negative diplococcus, Neisseria gonorrhoeae.

This cervical smear photomicrograph reveals extracellular diplococci determined to be Neisseria gonorrhoeae bacteria.

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