Document Detail


Temperature adaptation of cytosolic malate dehydrogenases of limpets (genus Lottia): differences in stability and function due to minor changes in sequence correlate with biogeographic and vertical distributions.
MedLine Citation:
PMID:  19112135     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
We characterized functional and structural properties of cytoplasmic malate dehydrogenases (cMDHs) from six limpets of the genus Lottia that have different vertical and latitudinal distributions. Particular attention was given to the cryptic species pair Lottia digitalis (northern occurring) and L. austrodigitalis (southern occurring) because of recent contraction in the southern range of L. digitalis and a northward range extension of L. austrodigitalis. As an index of adaptation of function, we measured the effects of temperature on the apparent Michaelis-Menten constant (K(m)) of the cofactor NADH (K(m)(NADH)). K(m)(NADH) values of cMDHs from the mid- to high-intertidal, low-latitude species L. scabra and L. gigantea were less sensitive to high temperature than those of cMDHs from the low- and mid-intertidal, high-latitude species L. scutum and L. pelta. cMDH of L. digitalis was more sensitive to high temperatures than the cMDH ortholog of L. austrodigitalis. Thermal stability (rate of loss of activity at 42.5 degrees C) showed a similar pattern of interspecific variation. Comparison of the deduced amino acid sequences showed that interspecific differences ranged from one to as many as 17 residues. Differences in K(m)(NADH) and thermal stability between orthologs of L. digitalis and L. austrodigitalis result from a single amino acid substitution. At position 291, the glycine residue in cMDH of L. digitalis is replaced by a serine in cMDH of L. austrodigitalis, a change that favors additional hydrogen bonding and reduced conformational entropy. This difference between closely related congeners demonstrates the role of minor alterations in protein sequence in temperature adaptation and suggests that such variation is important in governing shifts in biogeographic range in response to climate change.
Authors:
Yunwei Dong; George N Somero
Related Documents :
10978735 - Purification and characterization of two hemolysins from stichodactyla helianthus.
18272295 - Sequencing, bioinformatic characterization and expression pattern of a putative amino a...
23406265 - Synthesis of the tripeptide domain of sanglifehrins using asymmetric phase-transfer cat...
3379055 - Complete amino acid sequence of canine cardiac calsequestrin deduced by cdna cloning.
19501395 - The inhibition of glioma growth in vitro and in vivo by a chitosan/ellagic acid composi...
9462405 - Assessment of combined bile acid and ph profiles using an automated sampling device in ...
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't; Research Support, U.S. Gov't, Non-P.H.S.    
Journal Detail:
Title:  The Journal of experimental biology     Volume:  212     ISSN:  0022-0949     ISO Abbreviation:  J. Exp. Biol.     Publication Date:  2009 Jan 
Date Detail:
Created Date:  2008-12-29     Completed Date:  2009-03-19     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  0243705     Medline TA:  J Exp Biol     Country:  England    
Other Details:
Languages:  eng     Pagination:  169-77     Citation Subset:  IM    
Affiliation:
Hopkins Marine Station, Department of Biology, Stanford University, Pacific Grove, CA 93950, USA.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Adaptation, Biological
Animals
Cytosol / enzymology
DNA, Complementary / genetics
Enzyme Stability
Gastropoda / enzymology*,  physiology
Geography
Kinetics
Malate Dehydrogenase / chemistry,  genetics*,  metabolism*
Models, Molecular
NAD / metabolism
Protein Conformation
Protein Denaturation
Sequence Homology, Amino Acid
Temperature
Chemical
Reg. No./Substance:
0/DNA, Complementary; 53-84-9/NAD; EC 1.1.1.37/Malate Dehydrogenase

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  Effects of cocaine on honey bee dance behaviour.
Next Document:  The influence of experience in orientation: GPS tracking of homing pigeons released over the sea aft...