The significance of D-amino acids in soil, fate and utilization by microbes and plants: Review and identification of knowledge gaps

TY - JOUR

T1 - The significance of D-amino acids in soil, fate and utilization by microbes and plants

T2 - Review and identification of knowledge gaps

AU - Vranova, Valerie

AU - Zahradnickova, Helena

AU - Janous, Dalibor

AU - Skene, Keith R.

AU - Matharu, Avtar S.

AU - Rejsek, Klement

AU - Formanek, Pavel

PY - 2012/5/1

Y1 - 2012/5/1

N2 - Background: D-amino acids are far less abundant in nature than L-amino acids. Both L-and D-amino acids enter soil from different sources including plant, animal and microbial biomass, antibiotics, faeces and synthetic insecticides. Moreover, D-amino acids appear in soil due to abiotic or biotic racemization of L-amino acids. Both L-and D-amino acids occur as bound in soil organic matter and as "free" amino acids dissolved in soil solution or exchangeably bound to soil colloids. D-amino acids are mineralized at slower rates compared to the corresponding L-enantiomers. Plants have a capacity to directly take up "free" D-amino acids by their roots but their ability to utilize them is low and thus D-amino acids inhibit plant growth. Scope: The aim of this work is to review current knowledge on D-amino acids in soil and their utilization by soil microorganisms and plants, and to identify critical knowledge gaps and directions for future research. Conclusion: Assessment of "free" D-amino acids in soils is currently complicated due to the lack of appropriate extraction procedures. This information is necessary for consequent experimental determination of their significance for crop production and growth of plants in different types of managed and unmanaged ecosystems. Hypotheses on occurrence of "free" D-amino acids in soil are presented in this review.

AB - Background: D-amino acids are far less abundant in nature than L-amino acids. Both L-and D-amino acids enter soil from different sources including plant, animal and microbial biomass, antibiotics, faeces and synthetic insecticides. Moreover, D-amino acids appear in soil due to abiotic or biotic racemization of L-amino acids. Both L-and D-amino acids occur as bound in soil organic matter and as "free" amino acids dissolved in soil solution or exchangeably bound to soil colloids. D-amino acids are mineralized at slower rates compared to the corresponding L-enantiomers. Plants have a capacity to directly take up "free" D-amino acids by their roots but their ability to utilize them is low and thus D-amino acids inhibit plant growth. Scope: The aim of this work is to review current knowledge on D-amino acids in soil and their utilization by soil microorganisms and plants, and to identify critical knowledge gaps and directions for future research. Conclusion: Assessment of "free" D-amino acids in soils is currently complicated due to the lack of appropriate extraction procedures. This information is necessary for consequent experimental determination of their significance for crop production and growth of plants in different types of managed and unmanaged ecosystems. Hypotheses on occurrence of "free" D-amino acids in soil are presented in this review.

KW - Derivatization

KW - Extraction

KW - Input

KW - Microorganisms

KW - Mineralization

KW - Plant growth

KW - Racemization

KW - Soil D-amino acids

KW - Uptake

UR - http://www.scopus.com/inward/record.url?scp=84860114195&partnerID=8YFLogxK

U2 - 10.1007/s11104-011-1059-5

DO - 10.1007/s11104-011-1059-5

M3 - Review article

AN - SCOPUS:84860114195

SN - 0032-079X

VL - 354

SP - 21

EP - 39

JO - PLANT AND SOIL

JF - PLANT AND SOIL

IS - 1-2

ER -