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
Filter
  • Keywords: shikimic acid; streptomycetes; immunosuppressant; polyketide  (1)
  • Prediction equation  (1)
Source
Material
Years
Keywords
  • 1
    Electronic Resource
    Electronic Resource
    The shikimic acid pathway and polyketide biosynthesis (1998)
    Springer
    Journal of industrial microbiology and biotechnology 20 (1998), S. 299-303 
    Details
    ISSN: 1476-5535
    Keywords: Keywords: shikimic acid; streptomycetes; immunosuppressant; polyketide
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: The shikimic acid pathway, ubiquitous in microorganisms and plants, provides precursors for the biosynthesis of primary metabolites such as the aromatic amino acids and folic acid. Several branchpoints from the primary metabolic pathway also provide aromatic and, in some unusual cases, nonaromatic precursors for the biosynthesis of secondary metabolites. We report herein recent progress in the analysis of two unusual branches of the shikimic acid pathway in streptomycetes; the formation of the cyclohexanecarboxylic acid (CHC)-derived moiety of the antifungal agent ansatrienin and the dihydroxycyclohexanecarboxylic acid (DHCHC) starter unit for the biosynthesis of the immunosuppressant ascomycin. A gene for 1-cyclohexenylcarbonyl-CoA reductase, chcA, which plays a role in catalyzing three of the reductive steps leading from shikimic acid to CHC has been characterized from Streptomyces collinus. A cluster of six open reading frames (ORFs) has been identified by sequencing in both directions from chcA and the putative role of these in CHC biosynthesis is discussed. The individual steps involved in the biosynthesis of DHCHC from shikimic acid in Streptomyces hygroscopicus var ascomyceticus has been delineated and shown to be stereochemically and enzymatically distinct from the CHC pathway. A dehydroquinate dehydratase gene (dhq) likely involved in providing shikimic acid for both DHCHC biosynthesis and primary metabolism has been cloned, sequenced and characterized.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1038/sj.jim.2900527
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Physiological responses to prolonged treadmill walking with external loads (1991)
    Springer
    European journal of applied physiology 63 (1991), S. 89-93 
    Details
    ISSN: 1439-6327
    Keywords: Energy cost ; Load carriage ; Prediction equation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Limited information is available regarding the physiological responses to prolonged load carriage. This study determined the energy cost of prolonged treadmill walking (fixed distance of 12 km) at speeds of 1.10 m·s−1, 1.35 m·s−1, and 1.60 m·s−1, unloaded (clothing mass 5.2 kg) and with external loads of 31.5 and 49.4 kg. Fifteen male subjects performed nine trials in random order over a 6-week period. Oxygen uptake (VO2) was determined at the end of the first 10 min and every 20 min thereafter. A 10-min rest period was allowed following each 50 min of walking. No changes occurred in VO2 over time in the unloaded condition at any speed. The 31.5 and 49.4 kg loads, however, produced significant increases (ranging from 10 to 18%) at the two fastest and at all three speeds, respectively, even at initial exercise intensities less than 30% VO2max. In addition, the 49.4 kg load elicited a significantly higher (P〈0.05) VO2 than did the 31.5 kg load at all speeds. The measured values of metabolic cost were also compared to those predicted using the formula of Pandolf et al. In trials where VO2 increased significantly over time, predicted values underestimated the actual metabolic cost during the final minute by 10–16%. It is concluded that energy cost during prolonged load carriage is not constant but increases significantly over time even at low relative exercise intensities. It is further concluded that applying the prediction model which estimates energy expenditure from short-term load carriage efforts to prolonged load carriage can result in significant underestimations of the actual energy cost.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00235175
    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...