abstract：:The gas chromatograph mass spectrometer instrument of the Viking mission has demonstrated the absence of organic compounds in the immediate surface layer of the two landing sites. The demonstration of the successful operation of the instrument (comparison of ground-based test data with those obtained during interplane...

journal_title：Journal of molecular evolution

authors： Biemann K

更新日期：1979-12-01 00:00:00

abstract：:Evaporation of a solution of thymidine plus either the exo or the endo diastereomer of uridine cyclic 2',3'-O, O-phosphorothioate (U greater than p(S) in 1,2-diaminoethane hydrochloride buffer gave the 2',5' and 3',5' isomers of (P-thio) uridylylthymidine (Up(S)dT) in a ratio of 1:2 with a combined yield of about 20%....

journal_title：Journal of molecular evolution

authors： Usher DA,Yee D

更新日期：1979-11-01 00:00:00

abstract：:The problem of determining the minimal phylogenetic tree is discussed in relation to graph theory. It is shown that this problem is an example of the Steiner problem in graphs which is to connect a set of points by a minimal length network where new points can be added. There is no reported method of solving realistic...

journal_title：Journal of molecular evolution

authors： Foulds LR,Hendy MD,Penny D

更新日期：1979-07-18 00:00:00

abstract：:Langley and Fitch (1974, 1976) have shown that the pattern of nucleotide substitutions in proteins is inconsistent with a Poisson process with constant rate. From this they conclude that the rate is temporally heterogeneous. It is pointed out in this note that a process which is temporally homogeneous but not a Poisso...

journal_title：Journal of molecular evolution

authors： Gillespie JH,Langley CH

更新日期：1979-06-08 00:00:00

abstract：:Soluble lead salts and a number of lead-containing minerals catalyze the formation of oligonucleotides from nucleoside 5'-phosphorimidazolides. The effectiveness of lead compounds correlates strongly with their solubility. Under optimal conditions we were able to obtain 18% of pentamer and higher oligomers from ImpA. ...

journal_title：Journal of molecular evolution

authors： Sleeper HL,Orgel LE

更新日期：1979-04-12 00:00:00

abstract：:The possibility of surface catalysed condensation of unsubstituted amino acids on kaolinite in aqueous systems at elevated temperatures was investigated; no evidence of clay catalysed polycondensation has been found. The thermodynamic feasibility of the hypothetical lysine/dilysine condensation reaction in the tempera...

journal_title：Journal of molecular evolution

authors： Flegmann AW,Scholefield D

更新日期：1978-12-29 00:00:00

abstract：:The phylogeny of the creatine kinase (CK, EC 2.7.3.2) isozyme loci and their differential tissue expressions were determined for representatives of 65 families of vertebrates, with emphasis on the fishes. The transition from the single creatine kinase locus, characteristic of certain echinoderms, to the two creatine k...

journal_title：Journal of molecular evolution

authors： Fisher SE,Whitt GS

更新日期：1978-10-27 00:00:00

abstract：:The codons in four mammalian messenger RNAs (rabbit beta hemoglobin, rat pre-proinsulin, rat pre-growth hormone and human chorionic somatomammotropin) show a predominance of C and G in third nucleotide positions. The C:U ratio is about 2 to 1, and the G:A ratio is about 4 to 1. The possibility is discussed that this d...

journal_title：Journal of molecular evolution

authors： Jukes TH

更新日期：1978-06-20 00:00:00

abstract：:We have implemented a routine procedure for screening protein sequences for evidence of intragenic duplications. We tested 163 protein sequences representing 116 superfamilies of unrelated proteins. Twenty superfamilies contain proteins with internal gene duplications. The intragenic duplications detected can be divid...

journal_title：Journal of molecular evolution

authors： Barker WC,Ketcham LK,Dayhoff MO

更新日期：1978-02-21 00:00:00

abstract：:When an aqueous solution (pH 7.0) of 3H deoxythymidine 5'-triphosphate, deoxythymidine 5'-phosphate, 4-amino-5-imidazolecarboxamide, cyanamide and ammonium chloride was dried and heated at 60 degrees C for 18 h, oligomers were obtained in a yield of approximately 80%. After the chemical degradation of any pyrophosphat...

journal_title：Journal of molecular evolution

authors： Sherwood E,Joshi A,Oró J

更新日期：1977-12-29 00:00:00

abstract：:Adenosine 5'-phosphoramidates form when solutions containing adenosine 5'-polyphosphates pnA (n greater than or equal to 3) or P1, P2-diadenosine 5'-diphosphate and amines are allowed to dry out. Mg ions catalyze these reactions. We have studied systems containing ammonia, imidazole, glycine, ethylenediamine and hista...

journal_title：Journal of molecular evolution

authors： Lohrmann R

更新日期：1977-11-25 00:00:00

abstract：:Fox and Woese (1975a) have shown that a model of 5S RNA secondary structure similar to the one originally derived for Chlorella 5S RNA can be generalized with relatively minor variations to all sequenced 5S RNA molecules, i.e. that corresponding base paired regions can be formed at approximately the same positions. We...

journal_title：Journal of molecular evolution

authors： Vigne R,Jordan BR

更新日期：1977-09-20 00:00:00

abstract：:Hemoglobin Vancouver is a new abnormal hemoglobin with an amino acid substitution of the normal aspartyl residue 73 of the beta chain by a tyrosyl residue. It was discovered in a man of Chinese descent in association with beta thalassemia. It was subsequently detected in a sister in association with normal Hb A. The o...

journal_title：Journal of molecular evolution

authors： Jones RT,Brimhall B,Pootrakul S,Gray G

更新日期：1976-12-31 00:00:00

abstract：:The mitochondrial genome of yeast (S. cerevisiae or S. carlsbergensis) appears to be formed by 60-70 genetic units, each one of which is formed by (1) a GC-rich sequence, possibly having a regulatory role; (2) a gene, and (3) an AT-rich spacer, which probably is not transcribed. Recombination in this genome appears to...

journal_title：Journal of molecular evolution

authors： Bernardi G

更新日期：1976-12-31 00:00:00

abstract：:Quantitative immunological comparisons of three avian proteins, transferrin, ovalbumin, and penalbumin, indicate that penguins are phylogenetically most closely related to loons, albatrosses, herons, and grebes. These data support the theory that the ancestors of penguins were flying oceanic birds and that flightlessn...

journal_title：Journal of molecular evolution

authors： Ho CY,Prager EM,Wilson AC,Osuga DT,Feeney RE

更新日期：1976-10-27 00:00:00

abstract：:The periodic protein collagen is of special interest for the study of the relationship which exists between the structure of a protein and that of its mRNA, because oligopeptides containing glycine, proline (hydroxyproline) and alanine occur with great frequency in it. Collagen is particularly rich in these amino acid...

journal_title：Journal of molecular evolution

authors： Bachra BN

更新日期：1976-08-03 00:00:00

abstract：:The stability of helical structures formed by polyuridylic acid with nucleosides and nucleotides derived from adenosine is not significantly affected by replacing hydroxyl groups by hydrogen, amino, or azido functions. Stability is affected by the position of the phosphate group. ...

journal_title：Journal of molecular evolution

authors： Gibbs DE,Orgel LE

更新日期：1976-06-23 00:00:00

abstract：:Comparisons of the amino acid compositions of the nitrogenase proteins from different organisms and their correlation with cross-reactivities and taxonomical data suggest an evolution within bacterial genomes rather than within plasmids. Comparisons of the amino acid compositions of nitrogenases and other ATP-ases sho...

journal_title：Journal of molecular evolution

authors： Kleiner D,Littke W,Bender H,Wallenfels K

更新日期：1976-03-29 00:00:00

abstract：:A reaction which oligomerizes nucleotides under possible prebiotic conditions has been characterized. Nucleoside monophosphate in the presence of cyanamide at acid pH condenses to form dithymideine pyrophosphate and phosphodiester bonded compounds. Imidazole compounds and activated precursors such as nucleoside tripho...

journal_title：Journal of molecular evolution

authors： Odom DG,Brady JT

更新日期：1975-11-04 00:00:00

abstract：:The previously given systems-theoretic model for the synthesis of optical antipodes (AD and AL) in strongly asymmetric yield, which shows mono-bistable behaviour depending on the degree of "openess" of the chemical reaction system is reconsidered for two equal compartments (subscripts 1 and 2 on A) with coupling by di...

journal_title：Journal of molecular evolution

authors： Seelig FF,Zielke R

更新日期：1975-10-29 00:00:00

abstract：:The local stability of unbranched biosynthetic pathways is examined by mathematical analysis and computer simulation using a novel nonlinear formalism that appears to accurately describe biochemical systems. Four factors affecting the stability are examined: strength of feedback inhibition, equalization of the values...

journal_title：Journal of molecular evolution

authors： Savageau MA

更新日期：1975-08-05 00:00:00

abstract：:Variation in structure among primate hemoglobins is associated with variation in function. This supports the hypothesis that most substitutions observed among homologous proteins in different species have been fixed by natural selection because they contribute to the fitness of the genotype. It does not support the co...

journal_title：Journal of molecular evolution

authors： Sullivan B

更新日期：1972-12-01 00:00:00

abstract：:Oligonucleotide cataloguing has been used to characterize a number of 5S RNA species from various Procaryotes. Such catalogs can be used to establish certain and detailed phylogenetic relationships among organisms. Confining attention at present to four Families of Procaryotes, theEnterobacteriaceae, theBacillaceae, t...

journal_title：Journal of molecular evolution

authors： Sogin SJ,Sogin ML,Woese CR

更新日期：1972-06-01 00:00:00