Major bacterial contribution to marine dissolved organic nitrogen

Science

Volumn 281, Issue 5374, 1998, Pages 231-234

  McCarthy, Matthew D ^a   Hedges, John I ^a   Benner, Ronald ^b  

^a UNIVERSITY OF WASHINGTON   (United States)

^b UNIVERSITY OF TEXAS   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

AMINO ACID; NITROGEN;

BACTERIA; DISSOLVED ORGANIC NITROGEN; NITROGEN CYCLE;

ARTICLE; MARINE ENVIRONMENT; NITROGEN METABOLISM; OCEANIC REGIONS; ORGANIC CHEMISTRY; PRIORITY JOURNAL;

BACTERIA (MICROORGANISMS);

EID: 0032504067     PISSN: 00368075     EISSN: None     Source Type: Journal    
DOI: 10.1126/science.281.5374.231     Document Type: Article

References (44)

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14. Most samples were prefiltered with an Amicon DC10 Ultrafiltration system with a 0.1-μm pore size polysulfone hollow-fiber filter, before isolation of UDOM [1 nm < UDOM < 0.1 μm]. The first set of Gulf of Mexico isolates (27°N, 95°W) was prefiltered with Nucleopore 0.2-μm cartridges as an alternate and independent method. Central Pacific samples were collected in April 1992 at 12°S, 135°W from 2 to 4000 m. Gulf of Mexico samples were collected on two separate cruises. In August 1991, the 10-m sample (1000 liters) was collected at 27°N, 95°W. In July of 1995, two very large integrated samples (4000+ liters) were collected from 2 and 400 m at regular intervals on a transect between Corpus Christi, Texas, and Key West, Florida. The North Sea surface sample was also integrated on a transect across the central North Sea in April 1995. Such very large sample sizes are compositionally representative, but result in substantial decreases in relative recovery (Table 1) due to high concentration factors (77).
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44. We thank G. Cowie for inspiration and help with amino acid analysis, B. Black for help with sample processing, H. P. Fitznar for sharing work in progress, C. Lee for valuable discussions and insight, and D. Bear for guidance and support.