gram-variable


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gram-variable

gram-positive bacteria that can become gram-negative after culturing.
References in periodicals archive ?
A Changes in vaginal flora, such as a decreasing normal presence of lactobacilli (large gram-positive rods) and an increased presence of other bacteria, particularly Gardnerella vaginalis (gram-negative to gram-variable pleomorphic rods), is associated with bacterial vaginosis (BV), the most common cause of vaginitis in women of reproductive age.
In this system, large Gram-positive rods (Lactobacillus morphotypes), small Gram-negative to gram-variable rods (Gardneralla vaginalis and Bacteroides morphotypes) and curved Gram-negative rods (Mobiluncus species) are quantitated and a summation score is obtained.
The culture grew a Gram-variable bacillus, identified at a reference laboratory as Tsukamurella spp, and a yeast, Trichosporon spp.
We studied the inhibitory effects of these plants against 15 other bacteria; six Gram-negative, six Gram-positive, and three Gram-variable bacteria (Table 3).
The aerobic blood culture bottle of the first sample obtained from the recipient and aerobic cultures of the third erythrocyte unit enabled isolation of the same gram-variable coccobacilli after incubation for 48 hours (Figure).
A gram-stained smear will show an altered vaginal flora, one filled with pleomorphic gram-negative to gram-variable rods and lacking in the normally present gram-positive lactobacilli.
After 4 days, a gram-variable polymorphic rod, named nimes373, grew from both aerobic culture vials and yielded very small polymorphic colonies on Columbia sheep blood and blood-chocolate agar plates (Bio-Rad, Marnes-la-Coquette, France).
4,10] Cells with variable wall thickness (eg, dividing cells and those undergoing autolysis) tend to yield a Gram-variable stain result.
To the Editor: Streptobacillus moniliformis is a facultatively anaerobic, pleomorphic, gram-variable bacillus often seen in chains and as long unbranched filaments.
In 2 published outbreaks, the Brucella isolate resisted decoloration and appeared as a gram-positive or gram-variable coccobacillus and thus was misidentified as micrococcus or a coryneform bacillus (14,29).