CHARACTERIZATION AND HABITATS OF BACTERIA AND YEASTS ISOLATED FROM LAKE VANDA IN ANTARCTICA (Eleventh Symposium on Polar Biology)

• Main Authors: ナガシマ ヒデユキ, ニシカワ ジロウ, マツモト ゲンキ, イイズカ ヒロシ, Hideyuki NAGASHIMA, Jiro NISHIKAWA, Genki I. MATSUMOTO, Hiroshi IIZUKA
• Format: Report
• Language: English
• Published: Proceeding 1990
• Subjects: Vanda; Lake Vanda; Antarc*; Antarctica; Polar Biology; Proceedings of the NIPR Symposium on Polar Biology
• Online Access: https://nipr.repo.nii.ac.jp/?action=repository_uri&item_id=5100; http://id.nii.ac.jp/1291/00005100/; https://nipr.repo.nii.ac.jp/?action=repository_action_common_download&item_id=5100&item_no=1&attribute_id=18&file_no=1

Several strains of bacteria and yeasts were isolated at various depths of a meromictic lake, Lake Vanda, to clarify their physiological properties in relation to their habitats. Gram-negative rods, strains T-1, T-2, T-6, T-14, 3B, and Pseudomonas sp. 3G, were isolated at depths of above 30m where the temperature is 5-7℃ and the chlorinity is low. T-1, T-6, 3B, and 3G grow aerobically below 27℃, optimally about 20℃ under low salt concentration (<1% NaCl). Gramnegative aerobic cocci, strains 13A-F, were isolated at a depth of 69m near the bottom where the temperature is 24℃ and the chlorinity is high, up to 76.5 g/kg. Strain 13A grows aerobically at 12-36℃, optimally about 30℃ under the addition of 0 to 10% NaCl to the culture medium. T-1, T-6, 3G, and 13A contain more than 81% of unsaturated fatty acids such as oleic acid (18:1) and palmitoleic acid (16:1). The yeast Candida sp. strains T-3, T-4, T-5, T-9, and T-11 isolated at a depth of 5 m grow below 25℃, optimally about 15℃. They are fermentable and can utilize various sugars such as glucose and sucrose. T-5 and T-9 have 74% and 86% of unsaturated fatty acids such as linoleic acid (18 :2), respectively. The presences of psychrophilic bacteria and yeasts in the water column (5-30m), and of halotolerant bacteria in the bottom water (69m) well correspond to the meromictic property of the lake.