Vergleichende Physiologie der Tiere

Urich, Klaus

doi:10.1007/bf02285735

Cited by 8 publications

(9 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In S. nudus, in contrast to other invertebrate phyla, ammonia is the only end product of N-metabolism (Urich, 1990). Recent study revealed a significant 10-15% decrease in ammonia excretion at the lowest pHe of 6.70 tested under both hypercapnic as well as normocapnic conditions (Langenbuch and Pörtner, 2002).…”

Section: Discussionmentioning

confidence: 99%

Effects of environmental hypercapnia on animal physiology: A 13C NMR study of protein synthesis rates in the marine invertebrate Sipunculus nudus

Langenbuch

Bock

Leibfritz

et al. 2006

Comparative Biochemistry and Physiology Part A: Molecular &

View full text Add to dashboard Cite

Global climate change is associated with a progressive rise in ocean CO 2 concentrations (hypercapnia) and, consequently, a drop in seawater pH. However, a comprehensive picture of the physiological mechanisms affected by chronic CO 2 stress in marine biota is still lacking. Here we present an analysis of protein biosynthesis rates in isolated muscle of the marine invertebrate Sipunculus nudus, a sediment dwelling worm living at various water depths. We followed the incorporation of 13 C-labelled phenylalanine into muscular protein via high-resolution NMR spectroscopy. Protein synthesis decreased by about 60% at a medium pH of 6.70 and a consequently lowered intracellular pH (pHi). The decrease in protein synthesis rates is much stronger than the concomitant suppression of protein degradation (60% versus 10-15%) possibly posing a threat to the cellular homeostasis of structural as well as functional proteins. Considering the progressive rise in ocean CO 2 concentrations, permanent disturbances of cellular protein turnover might seriously affect growth and reproductive performance in many marine organisms with as yet unexplored impacts on species density and composition in marine ecosystems.

show abstract

Section: Discussionmentioning

confidence: 99%

Effects of environmental hypercapnia on animal physiology: A 13C NMR study of protein synthesis rates in the marine invertebrate Sipunculus nudus

Langenbuch

Bock

Leibfritz

et al. 2006

Comparative Biochemistry and Physiology Part A: Molecular &

View full text Add to dashboard Cite

show abstract

“…toxins or fragments thereof could be detected in extracts of faeces as well as haemolymph and fat body. The major bands found in the haemolymph and fat body of older larvae most probably represent storage proteins (‘larval haemolymph proteins’) which are typical of late larval instars ( Urich 1990; Deml 1993). Because, in most cases, the larvae fed with toxin died earlier than the control larvae, it is not surprising that these storage proteins can be found nearly exclusively in the control insects investigated.…”

Section: Discussionmentioning

confidence: 99%

Effects of Bacillus thuringiensisδδ‐endotoxins on food utilization, growth, and survival of selected phytophagous insects

Deml

Meise

Dettner

1999

J Applied Entomology

View full text Add to dashboard Cite

Feeding experiments using the Bacillus thuringiensisδ‐endotoxins, CryIA(c) and CryIIIA, were conducted with herbivorous insects from various orders (Lepidoptera, Coleoptera, Homoptera) in the laboratory. The mortality data obtained indicate a species‐specific susceptibility of the insects to the toxins whereby the feeding habits of the given animal seem to play a negligible part. An unexpected, severely damaging effect of CryIIIA on caterpillars was established, for the first time. By computing various development and nutritional indices it could be shown that retarded growth of the insects tested may not only be traced back to reduced feeding but also to a decreased utilization of food containing an endotoxin. The insect gut seems to be the site of operation and of storage or complete degradation of the endotoxins because neither in the faeces nor in the haemolymph and fat body, could the toxins and their degradation products, respectively, be detected hitherto by means of gel electrophoreses. An altering effect of the toxins on the gut‐microflora pattern is indicated from the first examinations but has to be further confirmed. Finally the applicability of these trials in corresponding examinations of transgenic plants producing B. thuringiensis toxin is dicussed.

show abstract

“…Cyanobacteria are prokaryotes and hence not only lack long-chained PUFAs (Phillips 1984), but furthermore do not contain sterols (Urich 1990), which are present in Scenedesmus (Rzama et al 1994). Sterols are indispensable for vital functions such as membrane fluidity, growth, and reproduction (Ederington et al 1995;Crockett 1998).…”

Section: Supplementation Of Fatty Acids and Lipids-mentioning

confidence: 99%

Supplementation of cyanobacterial food with polyunsaturated fatty acids does not improve growth of Daphnia

Elert

Wolffrom

2001

Limnology & Oceanography

121

View full text Add to dashboard Cite

The hypothesis that the low food quality of nontoxic, ingestible cyanobacteria for Daphnia is due to the absence of long‐chained polyunsaturated fatty acids (PUFAs) was tested. Synechococcus elongatus, which is well assimilated by Daphnia and is deficient in PUFAs, was chosen as a model food organism. A newly devised method was used to load single fatty acids and mixtures of fatty acids on beads of bovine serum albumin, which then were added as supplements to cyanobacterial suspensions. Growth rates of juvenile Daphnia galeata on Synechococcus elongatus were low and were not enhanced by the addition of C18‐PUFAs and C20‐PUFAs singly or together on beads. Supplementation of lipids from the green alga Scenedesmus obliquus significantly enhanced growth of D. galeata, indicating that the low quality of cyanobacterial carbon is due to a deficiency in a lipid other than PUFAs. The low food quality of Synechococcus elongatus was partly mitigated when the animals first fed on Scenedesmus obliquus, suggesting that the storage of algal lipids provides a mechanism to cushion the effect of short episodes of cyanobacterial dietary deficiencies on the growth of D. galeata.

show abstract

Vergleichende Physiologie der Tiere

Cited by 8 publications

References 0 publications

Effects of environmental hypercapnia on animal physiology: A 13C NMR study of protein synthesis rates in the marine invertebrate Sipunculus nudus

Effects of environmental hypercapnia on animal physiology: A 13C NMR study of protein synthesis rates in the marine invertebrate Sipunculus nudus

Effects of Bacillus thuringiensisδδ‐endotoxins on food utilization, growth, and survival of selected phytophagous insects

Supplementation of cyanobacterial food with polyunsaturated fatty acids does not improve growth of Daphnia

Contact Info

Product

Resources

About