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Spectral studies of lactose repressor protein modified with nitro phenol reporter groups


, : Spectral studies of lactose repressor protein modified with nitro phenol reporter groups. Journal of Biological Chemistry 252(10): 3153-3159

The spectral characteristics of lactose repressor protein [from Escherichia coli] modified with 2 nitrophenol reporter groups were determined. Reaction of 2-chloromercuri-4-nitrophenol with repressor increases the apparent pK of the nitrophenol from 6.75 to 8.3 and alters the wavelength of maximum absorption. Subsequent binding of inducer shifts the apparent pK toward slightly more acid pH. The pK values of the nitrophenol groups introduced into the repressor by reaction with 2-bromoacetamido-4-nitrophenol could not be determined, since they are below pH 7.0 where repressor is unstable. Titration of the nitrophenol chromophores indicates that the protein structure may undergo transitions as a function of pH. The binding of inducer to the repressor protein results in conformational changes which are reflected in spectral alterations for the nitrophenol groups. The mercurinitrophenols undergo a shift in the wavelength of maximum absorption to shorter wavelength, interpreted as reflecting an environmental alteration which results in more polar surroundings. Conversely, the nitrophenol groups introduced by the alkylating agent have a shift of wavelength of maximum absorption to longer wavelength, apparently experiencing a less polar environment. The positions of the nitrophenol groups in the primary structure of the protein and these spectral observations are correlated. Anti-inducers and a neutral compound also bind to the repressor protein, eliciting similar spectral changes; these alterations are different from those observed for inducers, as predicted from the different effects of these ligands on the function of the protein. The rates of the spectral transitions in response to inducers were measured and were of 2nd order. The rates are similar to those observed previously for other chromophores/fluorophores and apparently reflect a concerted, rapid change in the structure of the protein on binding to inducers.

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Accession: 006459932

PMID: 16884

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Reddy, C.V.R.; Cheriparambill, K.; Saul, B.; Makan, M.; Kassotis, J.; Kumar, A.; Das, M.Kumar., 2006: Fragmented left sided QRS in absence of bundle branch block: sign of left ventricular aneurysm. A left ventricular aneurysm (LVA) occurs between 3.5% and 9.4% of all cases of acute myocardial infarction. A fragmented left sided QRS (RSR; pattern or its variant RSr;, rSR;, or rSr;) without evidence of bundle branch block (QRS duration &lt...

Gavilan J.; Gavilan C.; Tejedor C., 1984: Application of the computer spectral analysis to the study of ocular mobility movements of pursuit. The clinical utilization of analog-digital computers allowed for the applications of spectral analysis methods to the study of the ocular movements. A series of programs in BASIC were developed that offer the possibility of strictly quantitatively...

Gole, V.C.; Torok, V.; Sexton, M.; Caraguel, C.G.B.; Chousalkar, K.K., 2015: Association between indoor environmental contamination by Salmonella enterica and contamination of eggs on layer farms. This study involves longitudinal and point-in-time surveys of Salmonella carriage and environmental contamination on two commercial cage layer farms positive for Salmonella enterica subsp. enterica serovar Typhimurium (flock A age, 32 weeks; flock...

Khapilova, V.I.; Chistyakova, I.A.; Averbakh, E.V., 1996: Corticosteroids in dermatology. Communication I. Systemic administration of corticosteroids. The paper summarizes clinical experience in systemic corticosteroid therapy of dermatoses. Absolute indications inclidea utoimmune skin disease, connective tissue lesions, systemic vasculitis, and allergic dermatoses. Systemic glucocorticoids are...

Muench, T.M.; White, M.R.; Wu, C.C., 1996: Visceral mycosis in Chinook salmon (Oncorhynchus tschawytscha) due to Sporobolomyces salmonicolor. One-month-old Chinook salmon fry from a cold-water hatchery were presented live for euthanasia and necropsy. Gross lesions were emaciation in 90% of the fry and ascites and increased cutaneous pigmentation in the remaining 10%. A cause for the ema...

Anonymous, 1976: Agricultural markets at the turn of 1976. Agrarwirtschaft 25 (12) 333-401

Vieira, P.; Danchin, E.G.J.; Neveu, Cédric.; Crozat, C.; Jaubert, Séphanie.; Hussey, R.S.; Engler, G.; Abad, P.; de Almeida-Engler, J.; Castagnone-Sereno, P.; Rosso, M-Noëlle., 2011: The plant apoplasm is an important recipient compartment for nematode secreted proteins. Similarly to microbial pathogens, plant-parasitic nematodes secrete into their host plants proteins that are essential to establish a functional interaction. Identifying the destination of nematode secreted proteins within plant cell compartment(s...

Nanda, D.; Minkoff, H.L., 1992: Pregnancy and women at risk for HIV infection. Special issues of pregnant women with HIV, such as HIV disease in pregnancy, transmission during pregnancy, transmission through breast milk, the effect of HIV disease on pregnancy outcome, and strategies for preventing neonatal damage from HIV, a...

Edroma, El, 1975: Wildlife count in a Uganda national park. Oryx(2): 176-178

Vita, P.D.; Vannucci, R., 1976: Multimode optical waveguides with graded refractive index: theory of power launching. The power launching into multimode optical fibers with any profile of refractive index is analyzed by means of the geometrical optics. First two formulas of the numerical aperture are obtained, one including and the other excluding the contributio...