34
CORDON A. RILEY
yielded these four plus glucuronic acid. Glucan and the water insoluble
polysaccharides were the most important constituents at all depths
and were virtually the only significant ones in deep water samples.
Handa used periodate oxidation to determine types of linkage. His
results will not be discussed in detail, but some generalities emerge. He
identified a 1,3-glucan which is similar to laminarin, and this general
class of compounds probably is derived from algal storage carbohydrates. The water insoluble carbohydrate is a mixture of polysaccharides having 1,2- or 1,4-linkages. The latter is a common constituent
of algal cell walls, and Handa believed that these polysaccharides are
a mixture of algal remains. Such material is more resistant to bacterial
attack than storage polysaccharides and is the chief component of deep
sea particulate carbohydrate.
Degens (1968) has presented a detailed examination of nitrogenous
compounds in particulate and dissolved matter and sediments at several
collection points in both the Atlantic and Pacific oceans. Total amino
acids in deep water particulate matter ranged from 5.3-1 8.6 pg/litre
and constituted more than 50% of total particulate matter. Major
amino acids included glycine, serine, glutamic acid, alanine, arginine,
lysine, and aspartic acid. The amino acid composition of particulate
matter was not markedly different from that of the so-called dissolved
fraction, and indeed the distinction between them is somewhat arbitrary. With regard to this subject and also the structural relations of
the nitrogenous molecules, a quotation from Degens is pertinent :
“Much confusion has also been generated due to the arbitrary
separation of particulate and dissolved matter into distinct classes of
compounds. Chemically speaking, such a classification has little
information content with regard to the elucidation of the molecular
nature of the organic compounds in the sea. The so-called dissolved
organic matter is composed of more than 90% of material that has a
molecular weight (MW) greater than 400. The bulk of the organic
compounds with MW > 400 falls in the 3 000-5 000 MW-range as
ascertained by molecular sieve techniques. Hydrolysation of this
material will release substantial amounts of monomers ; yet, some high
molecular weight products are still intact after this treatment.
“ The generally low C : N ratios of dissolved organic matter, the
presence of urea even after hydrolysis, the high abundance of amino
acids and aromatic compounds in connection with the high yields of
oxygen, suggest that oxygen and nitrogen are used in the structural
stabilization of the high molecular weight fraction. Peptides do
account for some of the materials. Urea may easily react with
aldehydes and produce long-chain polymers ; alternatively, its oxy-
CORDON A. RILEY
yielded these four plus glucuronic acid. Glucan and the water insoluble
polysaccharides were the most important constituents at all depths
and were virtually the only significant ones in deep water samples.
Handa used periodate oxidation to determine types of linkage. His
results will not be discussed in detail, but some generalities emerge. He
identified a 1,3-glucan which is similar to laminarin, and this general
class of compounds probably is derived from algal storage carbohydrates. The water insoluble carbohydrate is a mixture of polysaccharides having 1,2- or 1,4-linkages. The latter is a common constituent
of algal cell walls, and Handa believed that these polysaccharides are
a mixture of algal remains. Such material is more resistant to bacterial
attack than storage polysaccharides and is the chief component of deep
sea particulate carbohydrate.
Degens (1968) has presented a detailed examination of nitrogenous
compounds in particulate and dissolved matter and sediments at several
collection points in both the Atlantic and Pacific oceans. Total amino
acids in deep water particulate matter ranged from 5.3-1 8.6 pg/litre
and constituted more than 50% of total particulate matter. Major
amino acids included glycine, serine, glutamic acid, alanine, arginine,
lysine, and aspartic acid. The amino acid composition of particulate
matter was not markedly different from that of the so-called dissolved
fraction, and indeed the distinction between them is somewhat arbitrary. With regard to this subject and also the structural relations of
the nitrogenous molecules, a quotation from Degens is pertinent :
“Much confusion has also been generated due to the arbitrary
separation of particulate and dissolved matter into distinct classes of
compounds. Chemically speaking, such a classification has little
information content with regard to the elucidation of the molecular
nature of the organic compounds in the sea. The so-called dissolved
organic matter is composed of more than 90% of material that has a
molecular weight (MW) greater than 400. The bulk of the organic
compounds with MW > 400 falls in the 3 000-5 000 MW-range as
ascertained by molecular sieve techniques. Hydrolysation of this
material will release substantial amounts of monomers ; yet, some high
molecular weight products are still intact after this treatment.
“ The generally low C : N ratios of dissolved organic matter, the
presence of urea even after hydrolysis, the high abundance of amino
acids and aromatic compounds in connection with the high yields of
oxygen, suggest that oxygen and nitrogen are used in the structural
stabilization of the high molecular weight fraction. Peptides do
account for some of the materials. Urea may easily react with
aldehydes and produce long-chain polymers ; alternatively, its oxy-