Report of the editors—2014

Co‐Editors: Yi‐Hau Chen (1 January 2014‐31 December 2016) Michael J. Daniels (1 January 2015‐31 December 2017) Jeanine Houwing‐Duistermaat (1 January 2013‐31 December 2015) Jeremy M.G. Taylor (retired in 2014) Executive Editor: Marie Davidian (1 January 2006‐31 December 2017)     

Temperature—composition phase diagram and gel properties of the gelatin—starch—water system

The gelatin-starch-water system has been studied at different temperatures, at a total biopolymer concentration of 5.0 wt%. The weight ratios (W) of gelatin/ starch used were 9:1, 8:2.4. 2:8, 1:9, with pH values between 5.82 (at W = 9:1) and 6.50 (at W = 1:9). The systems were characterized rheologically and by turbidity measurements to construct a phase diagram in the temperature (T) and composition (W) variables. The T-W quadrant consists of three regions: a singlephase solutions region (A) and regions of complete and incomplete phase separation (B and C, respectively). The system in region C is a gel. Region B, lying between A and C, corresponds to two co-existing liquid phases. The transition from A to C (obtained by cooling the system at constant W) involves crossing region B. The properties of the resulting gels depend on the rate of this intersection. Gels formed on rapid cooling have an even distribution of turbidity, whereas slow cooling gives two gel layers of different turbidity. The gelation temperature and gel strength of the mixed systems are dominated by the gelatin component, with no indication of network formation by starch.     

Bioluminescence and chemiluminescence literature—Luciferase reporter genes—Lux and Luc

The following references encompass a review of recent literature where the in vivo expression of eukaryotic and/or prokaryotic luciferases provide for sensitive reporters of cellular activity. The list is subdivided into prokaryotic and eukaryotic applications. We have included the uses of luciferases in elucidating the control of gene expression or for monitoring cell viability. We have not included papers cited by Stanley and Stewart (J Biolumin Chemilumin 1990; 5:141–52) nor have we included papers on the structure and regulation of luciferases as this now substantial literature will be the subject of a future review. References cited in both this review and previous ones are referred to by the number assigned to them in the earlier review.     

Di-iron—carboxylate proteins

Di-iron centers bridged by carboxylate residues and oxide/hydroxide groups have so far been seen in four classes of proteins involved in dioxygen chemistry or phosphoryl transfer reactions. The dinuclear iron centers in these proteins are coordinated by histidines and additional carboxylate ligands. Recent structural data on some of these enzymes, combined with spectroscopic and kinetic data, can now serve as a base for detailed mechanistic suggestions. The di-iron sites in the major class of hydroxylase-oxidase enzymes, which contains ribonucleotide reductase and methane monooxygenase, show significant flexibility in the geometry of their coordination of three or more carboxylate groups. This flexibility, combined with a relatively low coordination number, and a buried environment suitable for reactive oxygen chemistry, explains their efficient harnessing of the oxidation power of molecular oxygen.     

Calcineurin—immunosuppressor complexes

Crystal structures of the Ser/Thr phosphatase calcineurin (protein phosphatase 2B) have recently been solved by X-ray crystallography, both in the free-protein state, and complexed with the immunophilin/immunosuppressant FKBP12/FK506. Core elements of the calcineurin phosphatase have been found to be similar to the corresponding elements of Ser/Thr phosphatase 1 and purple acid phosphatase. The structures provide a basis for understanding calcineurin inhibition by a ternary complex of immunophilin and immunosuppressant proteins.     

Caldesmon: A calmodulin — Binding actin — Regulatory protein

The protein caldesmon, originally isolated from smooth muscle tissue where it is the most abundant calmodulin-binding protein, has since been shown to have a wide distribution in actin- and myosin- containing cells where it is localized in sub-cellular structures concerned with motility, shape changes and exo- or endo-cytosis. Caldesmon is believed to be an actin- regulatory protein, and binds with high affinity to actin or actin-tropomyosin. Caldesmon inhibits the activation by actin-tropomyosin of myosin MgATPase activity, and the inhibition can be reversed by Ca2+.calmodulin. The binding of caldesmon to smooth muscle proteins has been studied in detail, enabling a model to be constructed which could account for the observed Ca2+ regulation of smooth muscle thin filaments. The abundance of caldesmon, and the Ca2+-regulation of its activity via calmodulin, mean that it is potentially an important intracellular regulator of processes such as smooth muscle contraction, cell motility and secretion.     

Intestinal parasitism—protozoa and helminths—in primates at the Barcelona Zoo

Abstract: The faunistic results regarding intestinal parasitism by protozoa and helminths in 21 primate species (three Cebidae, thirteen Cercopithecidae, one Hylobatidae, one Lemuridae, three Pongidae) are reported. The primate species were housed in four separate galleries. Six faecal samples of each host species were subjected to coprological analysis. Fifteen parasite species were detected: 11 protozoa (Entamoeba coli, E. chattoni, E. hartmanni, Iodamoeba bütschlii, Endolimax nana, Giardia intestinalis, Chilomastix mesnilii, Enteromonas hominis, Trichomonas intestinalis, Balantidium coli, and Blastocystis hominis) and 4 helminths (Ancylostoma sp., Strongyloides fuelleborni, Strongyloides sp., and Trichuris trichiura). The results reveal certain parasitic similarities between host species housed in the same gallery; however, these primate species do not always carry identical parasite species.