Bacterial bioluminescence models

Eckstein, J. W., Hastings, J. W., and Ghisla, S. (1993). Mechanism of bacterial bioluminescence. 4a,5-Dihydroflavin analogs as models for luciferase hydroperoxide intermediates and the effect of substituents at the 8-position of flavin on luciferase kinetics. Biochemistry 32 404 111. 

Mager HIX, Sazou D, Liu YH, Tu S-C, Kadish KM. Reversible one-electron generation of 4 5-substituted flavin radical cations Models for a postulated key intermediate in bacterial bioluminescence. J Am Chem Soc 1988 110 3759-62. 

Newman and Clements (2008) reanalyzed the binary metal mixture effect on bacterial bioluminescence data of Ownby and Newman (2003) using these models (Figure 1.8). A common slope was anticipated if two mixed metals were... 

A combination of univariate statistics and plots allow exploration of a candidate model relative to these last two requirements. Bacterial bioluminescence 15-minute EC50 data for 20 metal ions (McCloskey et al. 1996, Appendix 8.1) and the recently developed softness index (Kinraide 2009) can be applied to illustrate this approach. The following statistical analysis system (SAS) code implements analyses with normality plots and tests of regression residuals (Figure 8.1 top). It also plots predicted and observed data (Figure 8.1 middle) and regression residuals versus the explanatory variable, 0, 0 (Figure 8.1 bottom). 

FIGURE 8.2 Results from the SAS code that implements AIC and MaUows s Cp statistic-based model selection for the bacterial bioluminescence inhibition by 20 metal ions using 6 candidate explanatory variables (see text for details). The model with the lowest AIC was that including the softness, covalence, and ionic indices (inset table). Application of Mallows s Cp statistic also results in selection of the model containing the softness, covalence, and ionic indices. 

Continuing with the bacterial bioluminescence inhibition example, the model including the softness, covalence, and ionic indices had a PRESS of 14.260 and a SSj-... 

Some models of the excitation reaction in bacterial bioluminescence seem to require a similar explanation [8]. 

Donovan, V., Model Studies in Bacterial Bioluminescence, D. Phil. Thesis, University of Sussex 1980... 

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