title: Deep-sea Rhodococcus sp. BS-15, lacking the phytopathogenic fas genes, produces a novel glucotriose lipid biosurfactant.
abstract: Glycolipid biosurfactant-producing bacteria were isolated from deep-sea sediment collected from the Okinawa Trough. Isolate BS15 produced the largest amount of the glycolipid, generating up to 6.31 ± 1.15 g l(-1) after 4 days at 20 °C. Glucose was identified in the hydrolysate of the purified major component of the biosurfactant glycolipid. According to gas chromatography/mass spectrometry analysis, the hydrophobic moieties in the major component were hexadecanoate, octadecanoate, 3-hydroxyhexadecanoate, 2-hydroxyoctanoate, and succinate. The molecular weight of the purified major glycolipid was calculated to be 1,211, while (1)H and (13)C nuclear magnetic resonance spectra confirmed that the major component consisted of 2 mol of α-glucoside and 1 mol of β-glucoside. The molecular structure was assigned as novel trisaccharide-type glycolipid biosurfactant, glucotriose lipids. The critical micelle concentration of the purified major glycolipid was 2.3 × 10(-6) M, with a surface tension of 29.5 mN m(-1). Phylogenetic analysis showed isolate BS15 was closely related to a Rhodococcus strains isolated from Antarctica, and to Rhodococcus fascians, a phytopathogen. PCR analysis showed that the fasA, fasB, fasC, fasD, fasE, and fasF genes, which are involved in phytohormone-like cytokinin production, were not present in the genome of BS15; however, analysis of a draft genome sequence of BS15 (5.5 Mb) identified regions with 31 %, 53 %, 46 %, 30 %, and 31 % DNA sequence identity to the fasA, fasB, fasC, and fasD genes, respectively.
authors: Department of Biotechnology and Environmental Chemistry, Kitami Institute of Technology, 165 Koen-cho, Kitami, Hokkaido, 090-8507, Japan, konishim@mail.kitami-it.ac.jp.
authors: Masaaki
authors: M
authors: Konishi
authors: Shinro
authors: S
authors: Nishi
authors: Tokuma
authors: T
authors: Fukuoka
authors: Dai
authors: D
authors: Kitamoto
authors: Tomo-O
authors: TO
authors: Watsuji
authors: Yuriko
authors: Y
authors: Nagano
authors: Akinori
authors: A
authors: Yabuki
authors: Satoshi
authors: S
authors: Nakagawa
authors: Yuji
authors: Y
authors: Hatada
authors: Jun-Ichi
authors: J
authors: Horiuchi
mesh_terms: D001426:Bacterial Proteins / Q000378:metabolism*; D005947:Glucose / Q000378:metabolism; D060086:Hydrothermal Vents; D008055:Lipids / Q000096:biosynthesis*; D010947:Plants, Toxic / Q000382:microbiology*; D012240:Rhodococcus / Q000145:classification* / Q000502:physiology*; D013045:Species Specificity; D013501:Surface-Active Agents / Q000378:metabolism*; D014306:Trioses / Q000096:biosynthesis*
chemical_list: D001426:Bacterial Proteins; D008055:Lipids; D013501:Surface-Active Agents; D014306:Trioses; D005947:Glucose