Library

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Slow evolution of transferrin and albumin in birds according to micro-complement fixation analysis (1974)
    Springer
    Journal of molecular evolution 3 (1974), S. 243-262 
    Details
    ISSN: 1432-1432
    Keywords: Transferrin ; Albumin ; Micro-Complement Fixation ; Protein Evolution ; Evolutionary Rates ; Birds ; Crocodilians
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Rabbit antisera were prepared to purified ovotransferrin from chicken (order Galliformes) and red-winged blackbird (order Passeriformes) and to purified serum albumin from chicken and rhea (order Rheiformes). Quantitative microcomplement fixation was used to compare these proteins immunologically with those of representatives of all 27 orders of birds. The average interordinal immunological distances were 123 units for transferrin and 53 units for albumin. Extensive intraordinal comparisons of transferrin among 51 species within the order Galliformes and 33 species within the order Passeriformes were also carried out. Values ranging from 0–75 immunological distance units were found within each order. Rabbit antisera to purified alligator albumin were also prepared and shown to react with representatives of all 27 orders of birds, the average immunological distance being 166 units. When the data presented here are considered in relation to the fossil record of birds, it appears that transferrin and albumin have evolved more slowly in birds than in other vertebrates. If prevailing interpretations of the fossil record are correct, transferrin has evolved 2–4 times as fast in mammals and snakes as in birds, while serum albumin has evolved about 3 times as fast in mammals, iguanids, crocodilians, and frogs as in birds. Published immunological and sequence comparisons of lysozyme and cytochromec are also consistent with a slower rate of evolution in birds than in other vertebrates. The implications of a general slowdown in the evolution of bird proteins are discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01796041
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    The molecular heterogeneity and diversity of reptilian keratins (1979)
    Springer
    Journal of molecular evolution 12 (1979), S. 331-347 
    Details
    ISSN: 1432-1432
    Keywords: Protein diversity ; Molecualr heterogeneity ; Keratin evolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Reptile keratins produce complex electrophoretic patterns, contain a number of size classes, and contain protein fractions analogous to the fractions found in other keratins. Thus, reptile keratins are similar to the heterogenous keratins of birds and mammals, and quite different from amphibian epidermal keratins. This heterogeneity may be related to the multiple functions performed by the epidermis of these organisms. The chemical diversity of reptile keratins seems to depend on the morphological differences between the tissues in which they occur. This situation is also found among these proteins in mammals and birds suggesting that keratin diversity is related to the morphological and presumably functional differentiation of epidermal tissues. The distribution of the keratin fractions in each tissue contributes to this diversity but the significance of these fractional differences is uncertain. A comparison of the half-cystine and glycine content of vertebrateα andØ keratins suggests that theα andØ proteins of reptiles may be related to the softα keratins of mammals and amphibians. Mammalian hard keratins probably represent a uniquely derived group of proteins which are unlike the other vertebrate keratins. The presence of a “high sulphur” matrix component in both hard mammalianα and reptilian Ø keratins may represent some form of molecular convergence which provides these distantly related proteins with similar physical or organizational properties.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01732028
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Correlation of protein electrophoretic pattern with morphology of normal and mutant feathers (1972)
    Springer
    Biochemical genetics 7 (1972), S. 87-93 
    Details
    ISSN: 1573-4927
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Abstract Differences are demonstrated in electrophoretic patterns of SCM proteins extracted from the shaft and vane between the plumulaceous and pennaceous portions of normal feathers. Supportive evidence for these differences is given by scanning electron micrographs. In various mutant feathers, the observed structural and electrophoretic differences were due to the distribution of plumulaceous and pennaceous parts, not to new proteins. Feather mutants appear to be due to regulatory gene changes rather than to structural gene products.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00487012
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Self-assembly of avian φ-keratins (1983)
    Springer
    The protein journal 2 (1983), S. 63-75 
    Details
    ISSN: 1573-4943
    Keywords: feather ; keratin ; filaments
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Solubilized proteins from avian epidermal structures are heterogeneous in sequence, share a common tertiary structure, and have similar tissue-specific molecular weights. The proteins, in the thiol (SH-) form, will self-associate in urea-free, neutral-pH, low-salt buffers and form tonofilaments indistinguishable from native filaments. The mechanics of these processes are similar to those of the α-keratins of various mammalian tissues, although the size and nature of the subunit, filament geometry, and relation to tissue morphology are different.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01025168
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Functional-morphological and biochemical correlations of the keratinized structures in the African Grey Parrot, Psittacus erithacus (Aves) (1986)
    Springer
    Zoomorphology 106 (1986), S. 103-114 
    Details
    ISSN: 1432-234X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Keratinized structures from the African Grey Parrot (feather, down, claw, scale, rhamphotheca, soft lingual epithelium, and lingual nail) were compard by combining biochemical and functional-morphological approaches. At the molecular level, the keratinized structures of Psittacus erithacus are organized essentially like those of other avian species. Correlations were established (or verified) between the mechanical properties of the tissues and the molecular size of the keratin monomers, between the mechanical properties and the x-ray diffraction patterns of the tissues, and between the Polyacrylamide gel electrophoresis (PAGE) patterns of the keratins and certain aspects of growth patterns of the structures. The keratin proteins of the lingual nail, described here for the first time, resemble those of the claw and rhamphotheca. Morphological, biochemical and functional differences between the lingual nail and the rest of the lingual epithelium were established.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00312112
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...