gram-negative

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gram-negative

 [gram-neg´ah-tiv]
losing the stain or decolorized by alcohol in Gram's method of staining; see Gram stain. This is a primary characteristic of bacteria having a cell wall composed of a thin layer of peptidoglycan covered by an outer membrane of lipoprotein and lipopolysaccharide.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.

gram-neg·a·tive

(gram-neg'ă-tiv), In this expression gram begins with lowercase g but Gram stain takes an uppercase G.
Refers to the inability of a type of bacterium to resist decolorization with alcohol after being treated with crystal violet. However, following decolorization, these bacteria can be readily counterstained with safranin, imparting a pink or red color to them when viewed by light microscopy. This reaction is usually an indication that the outer structure of the bacterium consists of a cytoplasmic (inner) membrane surrounded by a relatively thin peptidoglycan layer, which in turn is surrounded by an outer membrane. See: Gram stain.
Farlex Partner Medical Dictionary © Farlex 2012

gram-negative

or

Gram-negative

(grăm′nĕg′ə-tĭv)
adj.
Of, relating to, or being a bacterium that does not retain the violet stain used in the Gram stain method.
The American Heritage® Medical Dictionary Copyright © 2007, 2004 by Houghton Mifflin Company. Published by Houghton Mifflin Company. All rights reserved.

gram-neg·a·tive

(gram-neg'ă-tiv)
Refers to the inability of a bacterium to resist decolorization with alcohol after being treated with Gram crystal violet. However, following decolorization, these bacteria can be readily counterstained with safranin, imparting a pink or red color to the bacterium when viewed by light microscopy.
See: Gram stain
Medical Dictionary for the Health Professions and Nursing © Farlex 2012

Gram-negative

see GRAM'S STAIN.
Collins Dictionary of Biology, 3rd ed. © W. G. Hale, V. A. Saunders, J. P. Margham 2005

Gram-negative

Refers to the property of many bacteria that causes them to not take up color with Gram's stain, a method which is used to identify bacteria. Gram-positive bacteria which take up the stain turn purple, while Gram-negative bacteria which do not take up the stain turn red.
Gale Encyclopedia of Medicine. Copyright 2008 The Gale Group, Inc. All rights reserved.

gram-neg·a·tive

(gram-neg'ă-tiv)
Refers to the inability of a type of bacterium to resist decolorization with alcohol after being treated with crystal violet.
Medical Dictionary for the Dental Professions © Farlex 2012
References in periodicals archive ?
All CecPs were bactericidal against Gram-positive such as Staplyococcus aureus, Bacillus subtilis, Micrococcus luteus, and Gramnegative bacteria, including Pesudomonas aeruginosa, Salmonella typhimurium and E.
Given that colonization with gramnegative bacteria is relatively uncommon, detecting such on endoscopic culture in acute exacerbations of chronic rhinosinusitis likely means that the patient has a true pathogenic infection, and antibiotic treatment can be considered.
Detection of beta-lactamases production in Gramnegative bacteria done with Screening of Strains with diameter of Zone of inhibition [less than or equal to] 27 mm for Cefotaxime (30 [micro]g), [less than or equal to] 22 mm for Ceftazidime (30 [micro]g) were considered as possible ESBL producers and selected and proceeded with confirmatory test as per CLSI guidelines such as Double disk diffusion synergy test (DDST), Phenotypic confirmatory disc diffusion test (PCDDT).
Fastidious, microaerophilic, helical shaped Gramnegative bacteria.
Antibiotics sensitivity profile compared with the crude extract activity against Gram-positive and Gramnegative bacteria AbAVG#G +ve AbAVG#G +ve Crude Extract 32.0 36.3 Tetracyline 28.7 29.0 Ciprofloxacin 35.0 32.7 Erythrimych 21.7 20.0 Vancomycin 18.0 15.7 Chloronophinicol 16.0 21.7 Amoxicillin/chavulnic 16.0 13.3 Amikacin 20.3 23.3 Note: Table made from bar graph.
Comparison of test methods for detecting metallo-p-lactamase-producing Gramnegative bacteria. Jpn J Infect Dis.
on the antimicrobial activity of Laetiporus sulphureus that showed that Gramnegative bacteria were less susceptible than Grampositive strains.
This was a poorly written article and while the overall conclusions about prevalence of ESBL Gramnegative bacteria may have some value, this was lost in the poor presentation and the clear discrepancies between the text and the data provided.
The uncommon features were tetracycline resistance mediated by tet(W), increasingly detected in gram-positive and in gramnegative bacteria (5) but never previously reported in S.