Structural differences between the Ca2+-ATPase enzymes of sarcoplasmic reticulum membrane from rabbit and carp muscles

1. Structural features were compared in sarcoplasmic reticulum Ca2+-ATPase enzymes from carp (Cyprinus carpio L.) and rabbit muscles. 2. Both membrane preparations contained the 105,000 mol. wt Ca2+ pump protein in high local density. 3. The tryptic cleavage of the carp enzyme gave different peptide fragments from those observed from rabbit enzyme. 4. Addition of vanadate, Ca2+ or lanthanides did not cause two-dimensional Ca2+-ATPase crystal formation, in contrast to the rabbit enzyme, which forms extensive arrays under these conditions. 5. No differences were found in this respect between microsome preparations derived from warm and cold adapted fishes. 6. A different primary sequence as well as a different disposition of the enzyme in the membrane may stand behind the observed dissimilarities.     

Erratum to: Rumen-protected conjugated linoleic acid supplementation to dairy cows in late pregnancy and early lactation: effects on milk composition,milk yield,blood metabolites and gene expression in liver

Background  

Conjugated linoleic acid (CLA) is a collective term for isomers of octadecadienoic acid with conjugated double-bond system. Thus, it was the objective to investigate whether milk composition and metabolic key parameters are affected by adding CLA to the diet of dairy cows in the first four weeks of lactation.     

PTC and PROP behave differently in tests of discrimination from their solvents

Better discrimination was possible between phenylthiocarbamide (PTC) solutions and the pure solvent when the solvent was a tasteless low- concentration NaCl solution to which the subject had adapted than when the solvent was purified water. The reverse was true for 6-n- propylthiouracil (PROP). The differences in discrimination for PROP and PTC in the different solvents were caused by differences in the intensity and persistence of aftertastes, rather than a more intense perception of the PTC and PROP tastes per se. This has consequences for traditional approaches to measuring taste sensitivity, as well as indicating that PTC and PROP are not necessarily equivalent indicators of 'taster' versus 'non-taster' status.