Open Access. Powered by Scholars. Published by Universities.®

Life Sciences Commons

Open Access. Powered by Scholars. Published by Universities.®

Biology

Selected Works

2012

Growth

Articles 1 - 3 of 3

Full-Text Articles in Life Sciences

Individual Cell Growth Rates Of Marine Bacteria, Measured By Bromodeoxyuridine Incorporation, Koji Hamasaki, Richard A. Long, Farooq Azam Oct 2012

Individual Cell Growth Rates Of Marine Bacteria, Measured By Bromodeoxyuridine Incorporation, Koji Hamasaki, Richard A. Long, Farooq Azam

Richard A. Long

We tested the application of 5-bromo-2’-deoxyuridine (BrdU), a thymidine analogue that becomes incorporated into DNA during growth, to measure growth rates of individual marine bacteria cells. Immunocytochemical detection of BrdU incorporation into bacterial DNA has the potential for single-cell-based growth measurement. Optimized procedure for immunocytochemistry was applicable to 14 marine heterotrophic bacterial isolates belonging to g-proteobacteria, α-proteobacteria, Cytophaga-Flavobacterium-Bacteroides (CFB) group and Gram-positive bacteria. The relationship between cell-specific fluorescence intensity and specific growth rate was linearly correlated among CFB group isolates, which indicated a potential of the method for quantitative measurement. Analysis of the detection limit indicated …


Coupling Between Bacterioplankton Species Composition, Population Dynamics, And Organic Matter Degradation, Jarone Pinhassi, Farooq Azam, Johanna Hemphälä, Richard A. Long, Josefina Martinez, Ulla Li Zweifel, Åke Hagström Oct 2012

Coupling Between Bacterioplankton Species Composition, Population Dynamics, And Organic Matter Degradation, Jarone Pinhassi, Farooq Azam, Johanna Hemphälä, Richard A. Long, Josefina Martinez, Ulla Li Zweifel, Åke Hagström

Richard A. Long

To study the effect of substrate addition on short term bacterial population dynamics and species composition in seawater mesocosms were maintained with water collected off Scripps Pier (La Jolla, California USA) Protein enrichment (BSA) triggered a dynamic response from the microbial food web, whereas enrichment with starch had no effect. In the protein enriched mesocosm the number of both nucleoid-containing cells and metabolically active cells increased by 3.0 X 105 cells ml-1 from Day 1 to Day 4 In the same time period the density of a set of 31 phylogenetically different bacteria (α- and g-Proteobactena as well as Flexibacter-Cytophaga-Bacteroides) …


In Vitro Plant Regeneration, Antioxidant And Antibacterial Studies On Broccoli, Brassica Oleracea Var. Italica, Rosna Binti Mat Taha Jan 2012

In Vitro Plant Regeneration, Antioxidant And Antibacterial Studies On Broccoli, Brassica Oleracea Var. Italica, Rosna Binti Mat Taha

Rosna Binti Mat Taha

Leaf and shoot tip explant of Brassica oleracea var. italica were inoculated on Murashige and Skoog (MS) basal medium supplemented with various concentrations of (BAP) and (IBA), alone and in combinations to achieve plant regeneration. Subsequently, antioxidant and antibacterial activities were determined from In vitro and In vivo plant parts. The highest mean numbers of shoot was observed on combinations of 1 mg l(-1) and 1.5 mg l(-1) of BAP and IBA, 9.49 and 8.69, respectively. The highest number of shoot produced (11.55) per shoot tip explant was recorded on 2.5 mg l(-1) BAP. In addition, highest percentage of roots …