The myoglobin of primates: the Night Monkey, Aotes trivirgatus (Cebidae,Platyrrhini, Anthropoidea)

The amino acid sequence of the myoglobin of the South American Night Monkey, Aotes trivirgatus, is identical to that of the marmoset (Callithrix jacchus [1]) except for residue 21 which is isoleucine in the marmoset, like in all other anthropoids, but valine in Aotes. Analysis of a possible pathway of the evolution of Aotes myoglobin using 18 known primate myoglobin sequences [2–5] supports the classification of the Night Monkey within Anthropoidea and Platyrrhini but it indicates that this species might be more closely related to the marmoset (family Callitrichidae) than to the family Cebidae as a member of which it is commonly classified.     

Interaction of a tryptophan-containing peptide with chromatin core particles. A fluorescence study

The binding of a tetrapeptide lysyltryptophylglycyllysine to nucleosome core particles has been investigated using UV absorption and fluorescence spectroscopy. Modifications of the absorption spectra and fluorescence quenching of the tryptophyl residue are consistent with stacking between the indole ring and nucleic acid bases. Therefore DNA interactions with histones do not prevent stacking of the tryptophyl residue with nucleic acid bases in the peptide-core particle complexes. The number of peptide binding sites is reduced to half that of naked DNA.     

山东蒙阴盆地常路组二段(古新世——早始新世)介形类化石

本文记述了2011年采自山东蒙阴盆地常路组二段的介形类化石共计6属10种4未定种,可建立一个Metacypris-Paracandona-Cyclocypris-Candona-Candoniella组合。根据介形类化石与国内已知化石组合对比研究,常路组二段的时代大致为古新世——早始新世。     

Mechanism of effector cell blockade. III. The increased sensitivity of neonatal PFC to effector cell blockade

The response to staphylococcal protein A (SPA) of unfractionated, T-cell-enriched (TCE), and T-cell-depleted (TCD) populations of both adult mononuclear cells (AMC) and cord blood mononuclear cells (CBMC) was studied. Adult unfractionated and TCE populations formed more T-lymphocyte colonies than did similar populations of CBMC. However, TCD populations of CBMC formed B-lymphocyte colonies at least as well as did the TCD population of AMC. These results suggest that B cells from CBMC may be more mature than CBMC T-cell populations.     

Membrane reconstitution in chl-r mutants of Escherichia coli K 12 VI. Morphological study of membrane assembly during complementation between extracts of chl-r mutants

The particles formed during the complementation between supernatant extracts of mutants chl A⁻ and chl B⁻ of Escherichia coli K 12 have been examined under the electron microscope. These particles look like membranous formations with a vesicular structure limited by a triple-layered membrane. The observations made on these particles at various incubation times during complementation show that the aggregation progresses through several stages of organization. When the phenomenon becomes steady, the population of reaggregated particles shows a large structural heterogeneity: it consists of small aggregates, filaments and particulary well-organized closed vesicles. As we had previously shown for the reconstitution of nitrate reductase, the rate of formation and the structure of newly formed aggregates depend on various parameters (temperature, dialysis).