Marine macroalgae, surrounding seawater, and surrounding sediment were collected at Weihai, China (122.
More...Marine macroalgae, surrounding seawater, and surrounding sediment were collected at Weihai, China (122.12 N, 37.56 E). Phycosphere bacteria: Macroalgae were cut into pieces and rinsed thrice with sterile seawater. Afterwards, 10 g of these pieces were washed with 10 ml sterile seawater (rotary shaker, 170 rpm., 30 min, 25 °C). One-milliliter aliquots were diluted stepwise to 1:100,000 (sterile seawater), and 100 μl were subsequently plated and incubated (21 d, 28 °C). Seawater samples: One-milliliter seawater was diluted stepwise with 9 ml sterile seawater to 1:1,000. Aliquots of 100 μl were then plated and incubated as described above.
Sediment samples: Sediment samples of 1 g were thoroughly mixed with 9 ml sterile seawater (rotary shaker, 170 rpm., 30 min, 25 °C) and then diluted in 1:10 steps with sterile seawater to 1:10,000. Afterwards, 100 μl aliquots were plated. Two media were used for plating, modified 2216E and modified VY/2 medium. Plating was completed within 2 h after sampling. After incubation, colony-forming units were counted with numbers ranging from 10 to 500. Colonies were selected depending on color, size, and shape. Picked colonies were purified by serial cultivation on plates with identical media. Purified strains were stored at -80 °C in a sterile 1% (w/v) saline medium with 15% (v/v) glycerol.
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