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Strain GP20-2(T) was isolated from a soil cultivated with ginseng in Korea. The 16S rRNA gene sequence of this strain showed the highest sequence similarity with Sphingomonas daechungensis CH15-11(T) (96.7%) and Sphingomonas sediminicola Dae 20(T) (96.2%) among the type strains. The strain GP20-2(T) was a strictly aerobic, Gram-negative, non-motile, rod-shaped bacterium that formed very tiny colonies, less than 0.3 mm in diameter after 10 days on R2A agar. The strain grew at 10-35-C (optimum, 35-C), at a pH of 5.0-8.0 (optimum, pH 6.0), and in the absence of NaCl. The DNA G+C content of strain GP20-2(T) was 67.2 mol%. It contained ubiquinone Q-10 as the major isoprenoid quinone, and summed feature 8 (C18:1ω6c and/or C18:1ω7c, 49.8%) and C16:0 (17.0%) as the major fatty acids. On the basis of evidence from our polyphasic taxonomic study, we concluded that strain GP20-2(T) should be classified as a novel species of the genus Sphingomonas, for which the name Sphingomonas parvus sp. nov. is proposed. The type strain is GP20-2(T) (=KACC 12865(T) =DSM 100456(T)).

In spite of their potential as biologically active compounds, the high molecular mass and viscous natures of fucoidans have hampered their applications especially as a therapeutic agent. Herein the fucoidan-degrading enzyme activities were partially purified from the cultured cells of Sphingomonas paucimobilis PF-1 mainly by ammonium sulfate precipitation. This enzyme preparation degraded fucoidans from the Korean Undaria pinnatifida sporophyll into several low-molecular weight fuco-oligosaccharides (LMFOs) with less than 3,749 Da. The FTIR spectra of intact fucoidan and mixture of LMFOs (1,389-3,749 Da) showed no significant structural difference except for about 10% reduced level of sulfate esters in LMFOs. The LMFOs have exerted strong anticoagulating activities at which the activated partial thromboplastin time (APTT) and thrombin time (TT) were significantly prolonged, although 3 approximately 20 times weaker activities were observed than those of intact fucoidan. In addition, unlike intact fucoidan, LMFOs did not affect significantly to the prothrombin time (PT). These results suggest that the partially purified fucoidan-degrading enzyme preparation is valuable for the production of fuco-oligosaccharides having anticoagulating activities, and that the molecular weight and/or sulfate content of the fucoidan from the Korean Undaria pinnatifida sporophyll could be important factors for its anticoagulating activity.