Low-molecular-weight organic molecules

EDTA is a low-molecular-weight organic molecule, ethylenediaminetetraacetate, that is commonly used as a proxy for marine DOM. It is acts as buffer, maintaining constant pH and/or metal ion concentrations in experimental solutions. 

For a highlight on asymmetric organo-catalysis by proline and other low-molecular weight organic molecules, see H. Groger, J. Wilken, Angew. 

Natural waters also contain a wide range of low-molecular-weight organic molecules (LMWOM), which are regarded as products of the microbial decomposition of, primarily, plant matter some have even been used as identifiers for certain genera of decomposers.123124... 

Although there has been some activity using metal ions as templates the overwhelming majority of studies have used low molecular weight organic molecules as templates. Metal ions which has been exploited are those which form a variety of well-defined coordination complexes, i.e. the transition metal... 

The light-induced oxidation of humic or fiilvic acid by Mn02 [and by Fe(III) (hydr)oxides] produces, in addition to Mn(II) [and Fe(II)], low molecular weight organic molecules that can serve as substrates for microorganisms (Sunda, 1994). 

Holoenzyme. Cofactors may be metal ions or low molecular weight organic molecules. A prosthetic group is a tightly bound cofactor that seldom dissociates from the enzyme. Cofactors that are loosely bound behave like cosubstrates they are easily bound and released from the enzyme. 

The VVOC and VOC are mostly due to non-bound, rather low molecular-weight organic molecules (also called as free or primary emissions) that exist in the system. 

Most spider neurotoxins characterized to date have been found to be low molecular weight organic molecules (inorganic ions and salts, free acids and ami-noacids, biogenic amines, neurotransmitters, and acylpolyamines), peptides, or proteins. Polyamines and a variety of polypeptides with a molecular mass ranging from 3000 to 8000 Da appear to represent the main toxic compounds in spiders. More than 60 peptide toxins have been described to date, whose presence can be confirmed by reversed-phase LC. Peptides can be easily distinguished from polyamines because of their different retention times and by ultraviolet detection using a diode-array detector. 

In MALDI mass spectrometry the analyte is mixed with low-molecular-weight organic molecules that are known for their abihty to absorb and transfer energy from the laser in the mass... 

Matrix-assisted laser desorption-ionization (MALDI) (Section 9.18A) A method in mass spectrometry for ionizing analytes that do not ionize well by electrospray ionization. The analyte is mixed with low molecular weight organic molecules that can absorb energy from a laser and then transfer this energy to the analyte, producing +1 ions which are then analyzed by the mass spectrometer. Mechanism (See Reaction mechanism)... 

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