WordNet

plan secretly, usually something illegal; "They plotted the overthrow of the government"
a small area of ground covered by specific vegetation; "a bean plot"; "a cabbage patch"; "a briar patch" (同)plot of land, plot of ground, patch
a secret scheme to do something (especially something underhand or illegal); "they concocted a plot to discredit the governor"; "I saw through his little game from the start" (同)secret plan, game
a chart or map showing the movements or progress of an object
the story that is told in a novel or play or movie etc.; "the characters were well drawn but the plot was banal"
devise the sequence of events in (a literary work or a play, movie, or ballet); "the writer is plotting a new novel"
United States frontierswoman and legendary figure of the Wild West noted for her marksmanship (1852-1903) (同)Martha Jane Burk, Burke, Martha Jane Burke, Calamity Jane

PrepTutorEJDIC

『小区画の土地』,小地所 / (小説・劇などの)『筋』,プロット / 『蔭謀』,たくらみ / 〈悪事〉‘を'『ひそかに計画する』,たくらむ / (地図・海図などに)…‘を'書き込む;…‘の'図表(図面)を作る / 〈土地〉‘を'区画する《+『out』+『名,』+『名』+『out』》 / (…に対して…の)『陰謀を企てる』,たくらむ《+『against』+『名』+『about』(『toward』)+『名』(do『ing』)

Wikipedia preview

出典(authority):フリー百科事典『ウィキペディア（Wikipedia）』「2015/03/29 10:39:30」(JST)

wiki en

In biochemistry, the Lineweaver–Burk plot (or double reciprocal plot) is a graphical representation of the Lineweaver–Burk equation of enzyme kinetics, described by Hans Lineweaver and Dean Burk in 1934.^[1]

Derivation

The plot provides a useful graphical method for analysis of the Michaelis–Menten equation:

Taking the reciprocal gives

where V is the reaction velocity (the reaction rate), K_m is the Michaelis–Menten constant, V_max is the maximum reaction velocity, and [S] is the substrate concentration.

Use

Lineweaver–Burk plots of different types of reversible enzyme inhibitors. The arrow shows the effect of increasing concentrations of inhibitor.

The Lineweaver–Burk plot was widely used to determine important terms in enzyme kinetics, such as K_m and V_max, before the wide availability of powerful computers and non-linear regression software. The y-intercept of such a graph is equivalent to the inverse of V_max; the x-intercept of the graph represents −1/K_m. It also gives a quick, visual impression of the different forms of enzyme inhibition.

The double reciprocal plot distorts the error structure of the data, and it is therefore unreliable for the determination of enzyme kinetic parameters. Although it is still used for representation of kinetic data,^[2] non-linear regression or alternative linear forms of the Michaelis–Menten equation such as the Hanes-Woolf plot or Eadie–Hofstee plot are generally used for the calculation of parameters.^[3]

When used for determining the type of enzyme inhibition, the Lineweaver–Burk plot can distinguish competitive, non-competitive and uncompetitive inhibitors. Competitive inhibitors have the same y-intercept as uninhibited enzyme (since V_max is unaffected by competitive inhibitors the inverse of V_max also doesn't change) but there are different slopes and x-intercepts between the two data sets. Non-competitive inhibition produces plots with the same x-intercept as uninhibited enzyme (K_m is unaffected) but different slopes and y-intercepts. Uncompetitive inhibition causes different intercepts on both the y- and x-axes .

Problems with the method

The Lineweaver–Burk plot is classically used in older texts, but is prone to error, as the y-axis takes the reciprocal of the rate of reaction – in turn increasing any small errors in measurement. Also, most points on the plot are found far to the right of the y-axis (due to limiting solubility not allowing for large values of [S] and hence no small values for 1/[S]), calling for a large extrapolation back to obtain x- and y-intercepts.^[4]

References

^ Lineweaver, H and Burk, D. (1934). "The Determination of Enzyme Dissociation Constants". Journal of the American Chemical Society 56 (3): 658–666. doi:10.1021/ja01318a036.
^ Hayakawa, K.; Guo, L.; Terentyeva, E.A.; Li, X.K.; Kimura, H.; Hirano, M.; Yoshikawa, K.; Nagamine, T. et al. (2006). "Determination of specific activities and kinetic constants of biotinidase and lipoamidase in LEW rat and Lactobacillus casei (Shirota)". J Chromatogr B Analyt Technol Biomed Life Sci 844 (2): 240–50. doi:10.1016/j.jchromb.2006.07.006. PMID 16876490.
^ Greco, W. R. and Hakala, M. T., (1979). "Evaluation of methods for estimating the dissociation constant of tight binding enzyme inhibitors," (PDF). J. Biol. Chem. 254 (23): 12104–12109. PMID 500698.
^ Dowd, John E.; Riggs, Douglas S. (1965). "A Comparison of Estimates of Michaelis–Menten Kinetic Constants from Various Linear Transformations". J. Biol. Chem 240 (2): 863–869.

External links

NIH guide, enzyme assay development and analysis

UpToDate Contents

全文を閲覧するには購読必要です。 To read the full text you will need to subscribe.

1. システマティックレビューおよびメタアナリシス systematic review and meta analysis
2. 生物統計学および疫学に関する一般用語集 glossary of common biostatistical and epidemiological terms
3. 心不全の病態生理：左心室の圧-容積とその他の血行動態の関係 pathophysiology of heart failure left ventricular pressure volume and other hemodynamic relationships
4. 自動血液分析装置 automated hematology instrumentation
5. フローボリューム曲線 flow volume loops

English Journal

α-Glucosidase inhibitor from Buthus martensi Karsch.

Kim SD.SourceDepartment of Chemical and Biological Engineering, Seokyeong University, Seoul 136-704, Republic of Korea. Electronic address: sdkim@skuniv.ac.kr.
Food chemistry.Food Chem.2013 Jan 15;136(2):297-300. doi: 10.1016/j.foodchem.2012.08.063. Epub 2012 Sep 7.
A bioassay-guided fractionation of an ethanol extract of Buthus martensi Karsch led to the isolation of a potent α-glucosidase inhibitor (compound S). The structure was elucidated as a novel β-carboline glucoalkaloid, harmanyl β-d-glucopyranoside, on the basis of spectral data, including (1)H NMR
PMID 23122061

Japanese Journal

Daedalin A, a Metabolite of Daedalea dickinsii, Inhibits Melanin Synthesis in an in Vitro Human Skin Model

MORIMURA Keiji,HIRAMATSU Kenji,YAMAZAKI Chihiro,HATTORI Yasunao,MAKABE Hidefumi,HIROTA Mitsuru
Bioscience, biotechnology, and biochemistry 73(3), 627-632, 2009-03-23
… A Lineweaver-Burk plot for a kinetic analysis indicates that 1 competed with L-tyrosine for tyrosinase. …
NAID 10027538686

Effects of Dimethylsulfoxide on Metabolism and Toxicity of Acetaminophen in Mice(Pharmacology)

YOON Mi Young,KIM Sun Ju,LEE Byung-Hoon,CHUNG Jin-Ho,KIM Young Chul
Biological & pharmaceutical bulletin 29(8), 1618-1624, 2006-08-01
… Lineweaver-Burk plot analysis indicated that the inhibition pattern produced by DMSO was competitive in nature. …
NAID 110005664000