An optical linewidth study of a chromoprotein-C-phycocyanin in a low-temperature glass

The temperature dependence of spectral holes burnt into a phycocyanin-doped ethylene glycol/water glass is investigated in the temperature range between 1.5 and 15 K. The data are well described by a power law with an exponent of 1.16 ± 0.1. Chromoproteins thus behave very much the same as glasses doped with small impurity molecules

Site-selective spectroscopy and level ordering in C-phycocyanin

We present a combined fluorescence and hole-burning study of the biliprotein C-phycocyanin. Sharp zero-phonon holes compare with a broad structureless fluorescence. This finding is rationalized in terms of the special level structure in this pigment, the fast energy-transfer processes and a lack of correlation of the energies of the emissive states

Sampling Field Heterogeneity at the Heme of c-Type Cytochromes by Spectral Hole Burning Spectroscopy and Electrostatic Calculations

AbstractWe report on a comparative investigation of the heme pocket fields of two Zn-substituted c-type cytochromes—namely yeast and horse heart cytochromes c—using a combination of hole burning Stark spectroscopy and electrostatic calculations. The spectral hole burning experiments are consistent with different pocket fields experienced at the hemes of the respective cytochromes. In the case of horse heart Zn-cytochrome c, two distinguishable electronic origins with different electrostatic properties are observed. The yeast species, on the other hand, displays a single electronic origin. Electrostatic calculations and graphics modeling using the linearized finite-difference Poisson-Boltzmann equation performed at selected time intervals on nanosecond-molecular dynamics trajectories show that the hemes of the respective cytochromes sample different potentials as they explore conformational space. The electrostatic potentials generated by the protein matrix at the heme show different patterns in both cytochromes, and we suggest that the cytochromes differ by the number of “electrostatic substates” that they can sample, thus accounting for the different spectral populations observed in the two cytochromes

Zur Genotyp-Umwelt-Interaktion von Fleischqualitätsmerkmalen bei unterschiedlichen Genotypen in ökologischer und konventioneller Schweinemast

Seven different pig breeds were kept under conventional and under organic feeding and housing conditions on two performance testing stations to analyse genotype-environment interactions for meat quality traits. Genetically controlled physical pork quality traits like pH- and EC-values are unaffected by both housing and feeding systems and no genotype-environment interaction could be found. In contrast, chemical meat characteristics like intramuscular fat content and fatty acid pattern are strongly influenced by genotype and feeding and a significant genotype-environment interaction. But no considerable reranking could be observed. The differences are caused by the differences in energy and amino acid supply between environments and variable lean meat synthesis capacity of the various genotypes. The significance is mainly generated by varying differences between environments within genotypes