Library

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
    ISSN: 1572-8773
    Keywords: Heme synthesis ; Iron metabolism ; Membranes ; Cation inhibition ; Metalloporphyrin
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology
    Notes: Summary Ferrochelatase in membrane preparations fromAzospirillum brasilense displayed an activity of 2.17 μmol protoheme formed · h−1 · mg protein−1 which is 10-fold greater than previous reports for other bacteria. This ferrochelatase showed an apparentK m of 20.9 μM for Fe2+, a pH optimum of 6.0–6.5, and stimulation by oleic or stearic acids. Co2+, Cu2+ and Zn2+ inhibited the incorporation of Fe2+ into protoporphyrin IX while Ni2 and Mg2+ had no effect on protoheme synthesis. Activity with Fe2+ and mesoporphyrin IX was less than with protoporphyrin IX but deuteroporphyrin IX produced the highest rate of protoheme synthesis. The membrane fraction containing ferrochelatase activity was found to insert Cu2+, Ni2+, Zn2+ and Co2+ enzymatically into protoporphyrin IX to produce metalloporphyrins. Cu2+ incorporation into protoporphyrin IX proceeded at a rate greater than with Fe2+ and theK m for Cu2+ was 21.9 μM.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 21 (1981), S. 1171-1172 
    ISSN: 0032-3888
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: The viscosities of suspensions of glass fibers in an aqueous solution of sucrose have been studied by use of a capillary viscometer. In the aligned condition in the capillary, the viscosity depends little on shear rate within the range studied or on fiber length, but increases with increasing volume fraction of the fibers. The entrance effect was found to depend strongly on fiber volume fraction and fiber length: this indicates that the suspensions are relatively resistant to flow during the initial stages while alignment takes place.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...