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Notes: Summary We have compared the amino acid sequences of cytochromec's from 45 species of organisms representing all five kingdoms, including one species each for the Protista and Monera. We have made a phylogeny for these data by reconstructing probable ancestral sequences which generate the present descendants through a minimum number of mutations. Several trials with different data sets produced the same minimal configuration. Assuming the occurrence of no major shifts in mutation acceptance rate, we find an early differentiation between prokaryote and eukaryote stocks. Afterward the eukaryote stem gave rise first to the protozoan flagellate branch and later to the multicellular green plant branch; after this the fungi and multicellular animal stems diverged from each other. A probable ancestral sequence was estimated for each kingdom of multicellular organisms. The basic eukaryote ancestor was probably a non-photosynthetic, heterotrophic flagellate. The photosynthetic apparatus could have been a later symbiotic acquisition in the plant ancestry. The dicotyledons had differentiated into two stocks before the emergence of a monocotyledon line as did the Ascomycetes before the emergence of the Basidiomycetes. The mollusc and chordate lines may have had a common acoelomate ancestor at the divergence of the arthropod stock. The numbers of mutations on all of the branches of the phylogenetic tree were calculated as well as the numbers of mutations and repeated mutations at each amino acid position.

Notes: We have studied 15 cases of cryptogenic fibrosing alveolitis stained with a monoclonal antibody reactive with human tumour necrosis factor-α (TNFα), a cytokine that has been implicated in inflammation and fibrosis. Seven were examples of lone cryptogenic fibrosing alveolitis and eight were examples of cryptogenic fibrosing alveolitis in patients with systemic sclerosis. There was widespread staining of epithelial cells, particularly hyperplastic type II pneumocytes. Macrophages stained only weakly. In a control group of 10 patients dying of unrelated conditions, staining for TNFα was weak and, in the alveolar epithelium, was confined to a very occasional type II pneumocyte. The strong expression of TNFα in hyperplastic type II pneumocytes suggests that TNFα produced during alveolar epithelial regeneration may play a part in the fibrosis seen in this disease.

Notes: Summary. Sera from patients with ovarian tumours were assayed for circulating immune complexes (CIC) by four well established assays based on the interaction of immune complexes with components of the complement system. There was no difference in control, pre- or post-operative or BCG-treated patients' sera. Levels were also unchanged in sera in antigen excess. In patients with ovarian tumours therefore the measurement of CIC would appear to be of little value as a screening test, as a guide to the extent of disease, prognosis or therapy. In a small pilot therapy-trial there was no difference in the survival rate between patients with stage III and IV ovarian cancer treated with cyclophosphamide plus BCG and those who received only cyclophosphamide. Treatment with BCG was associated with postoperative pyrexia and a prolonged hospital stay.

Notes: A versatile crystal cooling device is described for macromolecular crystallographic applications in the 290 to 80 K temperature range. It utilizes a fluctuation-free cold-nitrogen-gas supply, an insulated Mylar crystal cooling chamber and a universal ball joint, which connects the cooling chamber to the goniometer head and the crystal. The ball joint is a novel feature over all previous designs. As a result, the device can be used on various rotation cameras, precession cameras and diffractometers. The lubrication of the interconnecting parts with graphite allows the cooling chamber to remain stationary while the crystal and goniometer rotate. The construction allows for 360° rotation of the crystal around the goniometer axis and permits any settings on the arcs and slides of the goniometer head (even if working at 80 K). There are no blind regions associated with the frame holding the chamber. Alternatively, the interconnecting ball joint can be tightened and fixed. This results in a set up similar to the construction described by Bartunik & Schubert [J. Appl. Cryst. (1982), 15, 277–231], where the cooling chamber rotates with the crystal. The flexibility of the systems allows for the use of the device on most cameras or diffractometers. This device has been installed at the protein crystallographic stations of the Synchrotron Radiation Source at Daresbury Laboratory and in the Laboratory of Molecular Biophysics, Oxford. Several data sets have been collected with processing statistics typical of data collected without a cooling chamber. Tests using the full white beam of the synchrotron also look promising.

Notes: [Auszug] The structure of the segment 1 domain of gelsolin, a protein that fragments actin filaments in cells, is reported in complex with actin. Segment 1 binds monomer using an apolar patch rimmed by hydrogen bonds in a cleft between actin domains. On the actin filament model it binds tangentially, ...

Notes: Summary Pre- and post-operative ovarian cancer patients' sera were examined for the presence or circulating immune complexes using a variety of assay procedures. In contrast to findings with breast cancer patients' sera, sera from patients with other gynaecological tumours or with preclinical disease diagnosed by cytology, no evidence was obtained to indicate that circulating immune complexes were associated with ovarian cancer.

Notes: Abstract Presently the sequences of more than 150 different kinds of proteins and nucleic acids are known from the many thousands thought to exist in all living creatures. Some few of these have occpied much the same functional niche within the living cell from near the beginning of life. In three of these latter, sequence evidence pointing to duplications of genetic material in a primitive ancestor is available and in the fourth other evidence suggests it. Such a duplication, shared by the many descendant species, permits us to locate the point of earliest time on an evolutionary tree and to infer the actual order of subsequent evolutionary events. The amounts of change which have occurred in each descendant line can be estimated with good confidence. Some inferences can be made of the structure of the ancestral duplicated sequence, the evolutionary mechanisms which have been operative on it, and the functional capacity of the organism in which it originated. We will describe new, sensitive, objective methods for establishing the probable common ancestry of very distantly related sequences and the quantitative evolutionary change which has taken place. These methods will be applied to the four families, and evolutionary trees will be derived where possible. Of the three families containing duplications of genetic material, two are nucleic acids: transfer RNA and 5S ribosomal RNA. Both of these structures are functional in the synthesis of coded proteins, and prototypes must have been present in the cell at the inception of the fundamental coding process that all living things share. There are many types of tRNA which recognise the various nucleotide triplets and the 20 amino acids. These types are thought to have arisen as a result of many gene duplications. Relationships among these types will be discussed. The 5S ribosomal RNA, presently functional in both eukaryotes and prokaryotes, is very likely descended from an early form incorporating almost a complete duplication of genetic material. The amount of evolution in the various lines can again be compared. The other two families containing duplications are proteins: ferredoxin and cytochrome c. Ferredoxin from photosynthetic and nonphotosynthetic bacteria shows clear evidence of a duplication of genetic material. This duplication is very possibly shared by the ferredoxin from plant plastids and the related adrenodoxin from mammalian mitochondria. If so, a chronology of the detalls of evolution of these groups can be inferred. From these examples of protein and nucleic acid sequence, we conclude that the amount of change in the bacterial lines is less than that in the eukaryote lines. Even though mutant bacteria are easily produced in the laboratory, though their evolutionary adaptation to new drugs is very rapid, and though new virulent strains often appear spontaneously, nevertheless the sequences of ancient structures in the wild types have changed less than those in the eukaryote lines. Cytochrome c sequences from many eukaryotes and the closely related cytochrome c2 fromRhodospirillum rubrum are known. Other types of cytochrome, such as c551 and c553, are probably related to these through gene duplication. Knowledge of enough of these structures to establish an early duplication will provide a time orientation for the cytochrome c evolutionary tree. This quantitative tree now contains sequences from animals, fungi, green plants, protozoa, and bacteria, examples from all five biological kingdoms.