Properties of a partially-purified preparation of the prostaglandin-forming oxygenase from sheep vesicular gland

The fatty acid oxygenase of sheep vesicular glands was solubilized with Tween-40 and purified 60-fold using ammonium sulfate precipitation and DEAE-cellulose chromatography. Glycerol (50%) stabilized the activity at all stages of purification and allowed long-term storage at −60°. The partially purified enzyme contained less than 0.7 nmoles of iron per mg of protein and less than 0.1 nmole of copper per mg of protein. Although the K_I values for aspirin, BL-2338, flurbiprofen and ibuprofen remained relatively unchanged during purification, the apparent K_I value for inhibition by indomethacin decreased from 120 to 2.7 μ$\text{M}$.     

Susceptibility of Freshly Picked Ear Corn to Invasion by Fungi

High-moisture ear corn held 9 days at 23 C remained free of visible mold or evidence of Aspergillus flavus invasion provided there was no mechanical damage of the kernels.     

Growth of T-Strain Mycoplasmas in Medium Without Added Urea: Effect of Trace Amounts of Urea and of a Urease Inhibitor

Urea is currently considered to be a requirement for the propagation of T-strain mycoplasmas. We report here the replication of T-strain 960 (ATCC 25023) in media prepared from dialyzed components with added putrescine and allantoin but without added urea, or in dialyzed medium containing small amounts of added urea. The least amount of urea which allowed growth in the medium without allantoin was above 10 mug/ml. The amount of urea estimated to contaminate the added allantoin or putrescine was 5 mug/ml or less, which is insufficient to support T-strain replication. T-strain 960 was grown in the presence of urea and the urease inhibitor acetohydroxamic acid AHA where the organisms multiplied at a slower rate in the presence of AHA than in its absence. Urea hydrolysis occurred with concomitant ammonia accumulation and pH increase in cultures with AHA added.     

Sexual segregation and its ontogeny in squirrel monkey social structure

Four groups of squirrel monkeys were observed to determine the primary basis of adult group structure. These studies included observations on (1) intact and gonadectomized males and females during and after breeding; (2) intact adults only; (3) subadults only; and, (4) a mixed group of adults and subadults. The spatial distribution of subjects in each group was used as a basic measure of social organization. It was found that for adults, regardless of hormonal status, between-sex distances were consistently greater than within-sex distances. This sexually segregated adult structure was largely attributable to the females' attaction to one another and overt rejection of the males. Subadults by themselves did not show any clear sexual segregation. However, in the presence of an adult structure, the subadults gradually manifested the segregated pattern of the adults by gravitating toward same-sex adults. These results indicate that the socialization process, rather than endogenous hormonal status, is the major determinant of adult social structure in squirrel monkeys.     

Protein synthesis in the cotyledons of Pisum sativum L. Protein factors involved in the binding of phenylalanyl-transfer ribonucleic acid to ribosomes

1. Proteinaceous factors contained in a 0.5m-KCl extract of ribosomes from pea cotyledons form a ternary complex at 0 degrees C with [(14)C]phenylalanyl-tRNA and poly(U). The complex is measured by its quantitative retention on Millipore filters. 2. Complex-assembly is optimal at 5mm-Mg(2+) and is independent of GTP and ribosomes. 3. The addition of ribosomes is required to stabilize the complex at 34 degrees C. The complex binds to a puromycin-sensitive site on the ribosome. 4. Soluble factors from the 250000g supernatant of pea cotyledon form a Millipore-retainable complex dependent on GTP and ribosomes. 5. Complex-formation by soluble factors has a Mg(2+) optimum of 10-12mm and forms a puromycin-insensitive complex with ribosomes. 6. The function of the ribosomal protein factors and the supernatant fraction in initiation of protein synthesis is discussed.     

The fossil evidence of anthropoid brain evolution

The endocast of Aegyptopithecus, a 27 million year old ape, reveals that its brain was advanced over that of prosimians and comparable to that of modern anthropoids in relative size and in having expanded visual cortex, reduced olfactory bulbs, and a central sulcus separating primary somatic sensory and motor cortex. The early appearance of those features suggests that they may have been among the adaptations responsible for the evolution of anthropoids from prosimian ancestors. The frontal lobe was relatively smaller in Aegyptopithecus than in modern anthropoids. An endocast of Dolichocebus, one of the oldest known New World monkeys (25–30 million years old), reveals visual cortex expanded as in modern anthropoids. The 19 million year old Napak frontal bone displays a hominoid rather than cercopithecoid sulcal pattern. An 18 million year old endocast of the ape Dryopithecus (Proconsul) was neither monkey-like nor primitive, as originally described, but rather apelike and essentially modern in all observable features. The oldest undoubted Old World monkey endocast, from nine million year old Mesopithecus, reveals that the brain was modern in sulcal pattern and proportions. The sulcal pattern was like that of modern colobines, but that appears to be the more primitive condition, from which features characteristic of modern cercopithecine brains have evolved. The brain of six million year old Libypithecus was similar to that of Mesopithecus. A two million year old endocast of “Dolichopithecus” arvernensis displays a modern cercopithecine sulcal pattern.     

Yields of Hydrogenomonas eutropha from Growth on Succinate and Fumarate

Molar growth yields were determined from chemostat cultures of Hydrogenomonas eutropha on succinate and on fumarate. The yields from culture on succinate were about 12 g higher than on fumarate. Assuming this difference to be equivalent to 1 molecule of adenosine triphosphate, it is concluded that the oxidation by oxygen of the Hydrogenomonas cytochrome b yields 1 molecule of adenosine triphosphate.     

PREPARATION AND CHARACTERIZATION OF A PLASMA MEMBRANE FRACTION FROM ISOLATED FAT CELLS

A rapid method of preparing plasma membranes from isolated fat cells is described. After homogenization of the cells, various fractions were isolated by differential centrifugation and linear gradients. Ficoll gradients were preferred because total preparation time was under 3 hr. The density of the plasma membranes was 1.14 in sucrose. The plasma membrane fraction was virtually uncontaminated by nuclei but contained 10% of the mitochondrial succinic dehydrogenase activity and 25–30% of the RNA and reduced nicotinamide adenine dinucleotide cytochrome c reductase activity of the microsomal fraction. Part of the RNA and NADH-cytochrome c reductase activity was believed to be native to the plasma membrane or to the attached endoplasmic reticulum membranes demonstrated by electron microscopy. The adenyl cyclase activity of the plasma membrane fraction was five times that of Rodbell's "ghost" preparation and retained sensitivity to epinephrine. The plasma membrane ATPase activity was five times that of the homogenate and microsomal fractions. Electron microscopic evidence suggested contamination of the plasma membrane fraction by other subcellular components to be less than the biochemical data indicated.