Incorporation of L-[U-14C]leucine into ergosine by cell-free extracts of Clavicepspurpurea (FR.) tul

A cell-free system of $\text{Claviceps}\text{purpurea}$ has been described which incorporates [¹⁴C] leucine into the peptide-type ergot alkaloid ergosine. Cell-free extracts may be prepared either from protoplasts or lyophilized mycelium. Production was markedly stimulated by addition of agroclavine compared with d-lysergic acid and by agitation of the incubation mixture. The synthesis of ergosine is strongly dependent on the presence of ATP in the reaction mixture.     

Primary structure of yeast proteinase B inhibitor 2.

The complete amino acid sequence of yeast proteinase B inhibitor 2 (IB2) was determined to be H3N+-Thr-Lys-Asn-Phe-Ile-Val-Thr-Leu-Lys-Lys-Asn-Thr-Pro-Asp-Val-Glu-Ala-Lys-Lys-Phe-Leu-Asp-Ser-Val-His-His-Ala-Gly-Gly-Ser-Ile-Leu-His-Glu-Phe-Asp-Ile-Ile-Lys-Gly-Tyr-Thr-Ile-Lys-Val-Pro-Asp-Val-Leu-His-Leu-Asn-Lys-Leu-Lys-Glu-Lys-His-Asn-Asp-Val-Ile-Glu-Asn-Val-Glu-Asp-Lys-Glu-Val-His-Thr-Asn-COO-. Elucidation of the primary structure was enabled by automated Edman degradation and COOH-terminal hydrolysis with carboxypeptidases A (bovine pancreas and Y (yeast). IB2 is the first proteinase inhibitor to be sequenced that possesses a structure devoid of disulfide bridges.     

D-Trp8-D-Cys14-somatostatin--demonstration of its differential suppressive activity in juvenile diabetics.

In 8 insulin-dependent diabetics, the effect of D-Trp8-D-Cys14-somatostatin on blood glucose, growth hormone, and glucagon levels as well as on insulin requirements from an artificial endocrine pancreas was studied during a balanced meal. The somatostatin analogue was infused at a rate of 25 microgram/h preceeded by a bolus injection of 25 microgram 30 minutes before ingestion of the meal. At this dose the analogue had no effect on glucagon levels and insulin requirements from the artificial pancreas. On the other hand, there was a significant lowering effect on fasting blood glucose levels, possibly indicating a direct inhibition of hepatic glucose production. Furthermore, there might be a slight effect on growth hormone levels, as was demonstrated by a rebound increase after termination of analogue infusion.     

The effect of three days of blood glucose normalization by means of an "artificial endocrine pancreas" on the concentrations of growth hormone, glucagon, and cortisol in juvenile diabetics.

Glucagon, growth hormone, and cortisol secretion was studied in seven male insulin-dependent diabetics under conventional subcutaneous insulin therapy and after three days of blood glucose normalization attained by the artificial endocrine pancreas (Biostator-GCIIS). The diurnal hormonal profiles under the two types of therapy were compared. Six healthy male students served as control group. A three-day period of blood glucose normalization in insulin-dependent diabetic can restore glucagon secretion to normal. Growth hormone secretion is decreased but not completely normalised. Cortisol secretion is slightly decreased. It is concluded that prolonged normoglycemia achieved by means of an artificial endocrine pancreas may completely control endocrine abnormalities in insulin-dependent diabetics.     

Cyclic 3',5'-adenosine monophosphate in the choroid plexus: stimulation by cholera toxin.

Cholera toxin was found to induce high accumulations of cyclic AMP in the isolated choroid plexus of the rabbit and in the incubation medium. The accumulation showed a characteristic lag phase of at least 30 min and continued for at least 3 hours. Inactivated cholera toxin was unable to increase cyclic AMP levels. There was only a moderate effect of cholera toxin on cyclic AMP “low K_m” phosphodiesterase activity in homogenates. The effect of cholera toxin on cyclic AMP levels confirms the existance of a potent cyclic AMP generating system in the choroid plexus which is activated also by β-adrenergic agonists, histamine and prostaglandin E₁.     

Pathology of Anopheles stephensi after infection with Plasmodium berghei berghei. II. Changes in amino acid contents.

Infection with Plasmodium berghei results in the disease of a relatively high percentage of mosquitoes depending on the experimental conditions. The damage caused by the parasites may be so severe that the host dies. It can also become manifest for instance in a change in the amino acid content of the mosquito homogenate. The amino acid content of mosquitoes fed on a glucose solution, normal mouse blood, or the blood of infected mice was analysed qualitatively and quantitatively over a period of 14 days. The amino acids lysine, phenylalanine, proline, threonine, and tyrosine are always found in higher concentrations in infected mosquitoes. The content of leucine (and/or isoleucine) increased from the 6th day and glutamic acid from the 9th day compared to the controls. Lower concentrations were found for alanine, aspartic acid, glycine, and serine as compared to uninfected mosquitoes. Further investigations on this subject might help to find the causes for the susceptibility or resistance of individual mosquitoes to plasmodia.     

Thermal ecology and baseline energetic requirements of a large‐bodied ectotherm suggest resilience to climate change

1. Most studies on how rising temperatures will impact terrestrial ectotherms have focused on single populations or multiple sympatric species. Addressing the thermal and energetic implications of climatic variation on multiple allopatric populations of a species will help us better understand how a species may be impacted by altered climates.
2. We used eight years of thermal and behavioral data collected from four populations of Pacific rattlesnakes (Crotalus oreganus) living in climatically distinct habitat types (inland and coastal) to determine the field‐active and laboratory‐preferred body temperatures, thermoregulatory metrics, and maintenance energetic requirements of snakes from each population.
3. Physical models showed that thermal quality was best at coastal sites, but inland snakes thermoregulated more accurately despite being in more thermally constrained environments. Projected increases of 1 and 2°C in ambient temperature result in an increase in overall thermal quality at both coastal and inland sites.
4. Population differences in modeled standard metabolic rate estimates were driven by body size and not field‐active body temperature, with inland snakes requiring 1.6× more food annually than coastal snakes.
5. All snakes thermoregulated with high accuracy, suggesting that small increases in ambient temperature are unlikely to impact the maintenance energetic requirements of individual snakes and that some species of large‐bodied reptiles may be robust to modest thermal perturbations under conservative climate change predictions.

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