کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
4395360 1618403 2015 10 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Differentiating the role of different-sized microorganisms in peptide decomposition during incubations using size-fractioned coastal seawater
ترجمه فارسی عنوان
تفاوت نقش میکروارگانیسم های مختلف در تجزیه پپتید در طی انکوباسیون ها با استفاده از آب دریایی ساحلی اندازه گیری شده
کلمات کلیدی
موضوعات مرتبط
علوم زیستی و بیوفناوری علوم کشاورزی و بیولوژیک علوم آبزیان
چکیده انگلیسی


• Tetrapeptide AVFA was incubated in size-fractioned coastal seawater.
• Gammaproteobacteria, mainly Alteromonas, played the dominant role in taking up small peptides.
• Decomposition rates of AVFA were significantly higher in large size fractions (> 5 μm).
• Large-size microorganisms like protists may have contributed to the decomposition of AVFA.

Peptide decomposition by different-sized microorganisms was compared by incubating tetrapeptide alanine–valine–phenylalanine–alanine (AVFA), a fragment of RuBisCO, in coastal seawater after size-fraction by filtration. The size-fractioned seawater included < 0.8-μm filtered (free-living bacteria), < 5-μm filtered (free-living bacteria + heterotrophic nanoflagellates), < 20-μm filtered (free-living and particle-attached bacteria + heterotrophic nanoflagellates + other small protists), and unfiltered whole water collected from Texas coast in the western Gulf of Mexico. Decomposition rates of AVFA in the < 20-μm and unfiltered seawater were significantly higher than those in the < 0.8-μm and < 5-μm seawater in the December 2011 incubation. The higher decomposition rate in the large size fractions can be attributed to activities of particle-attached bacteria and/or large-size microorganisms, such as osmotrophic protists. However, the role of particle-attached bacteria in explaining this decomposition difference might be limited, as bacterial abundance and community structure did not differ much among the 4 treatments. Consistently, the June 2013 incubation indicated that AVFA decomposed most rapidly in the unfiltered seawater with > 20-μm microorganisms. This study provides insights into the relative role of different-sized microorganisms in regulating the recycling of labile organic matter in coastal waters.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Experimental Marine Biology and Ecology - Volume 472, November 2015, Pages 97–106
نویسندگان
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