Quantitative and functional posttranslational modification proteomics reveals that TREPH1 plays a role in plant touch-delayed bolting.

Environmental mechanical forces, such as wind and touch, trigger gene-expression regulation and developmental changes, called "thigmomorphogenesis," in plants, demonstrating the ability of plants to perceive such stimuli. In Arabidopsis, a major thigmomorphogenetic response is delayed bolting, i.e., emergence of the flowering stem. The signaling components responsible for mechanotransduction of the touch response are largely unknown. Here, we performed a high-throughput SILIA (stable isotope labeling in Arabidopsis)-based quantitative phosphoproteomics analysis to profile changes in protein phosphorylation resulting from 40 seconds of force stimulation in Arabidopsis thaliana Of the 24 touch-responsive phosphopeptides identified, many were derived from kinases, phosphatases, cytoskeleton proteins, membrane proteins, and ion transporters. In addition, the previously uncharacterized protein TOUCH-REGULATED PHOSPHOPROTEIN1 (TREPH1) became rapidly phosphorylated in touch-stimulated plants, as confirmed by immunoblots. TREPH1 fractionates as a soluble protein and is shown to be required for the touch-induced delay of bolting and gene-expression changes. Furthermore, a nonphosphorylatable site-specific isoform of TREPH1 (S625A) failed to restore touch-induced flowering delay of treph1-1, indicating the necessity of S625 for TREPH1 function and providing evidence consistent with the possible functional relevance of the touch-regulated TREPH1 phosphorylation. Taken together, these findings identify a phosphoprotein player in Arabidopsis thigmomorphogenesis regulation and provide evidence that TREPH1 and its touch-induced phosphorylation may play a role in touch-induced bolting delay, a major component of thigmomorphogenesis.

Single-nucleotide polymorphisms and haplotype of CYP2E1 gene associated with systemic lupus erythematosus in Chinese population.

INTRODUCTION: Cytochrome P-450 2E1 (CYP2E1) is an important member of the CYP superfamily, which is involved in the metabolism and activation of many low molecular weight toxic compounds. We tried to investigate the possible association of CYP2E1 tag single nucleotide polymorphisms (SNPs) with susceptibility to systemic lupus erythematosus (SLE) in a Chinese Han population. METHODS: The coding and flanking regions of the CYP2E1 gene were scanned for polymorphisms and tag SNPs were selected. A two-stage case-control study was performed to genotype a total of 876 SLE patients and 680 geographically matched healthy controls (265 cases and 288 controls in stage I and 611 cases and 392 controls in stage II). SLE associations of alleles, genotypes and haplotypes were tested by age and sex adjusted logistic regression. The gene transcription quantitation was carried out for peripheral blood mononuclear cell (PBMC) samples from 120 healthy controls. RESULTS: Tag SNP rs2480256 was found significantly associated with SLE in both stages of the study. The "A" allele was associated with slightly higher risk (odds ratio (OR) = 1.165, 95% confidence interval (CI) 1.073 to 1.265, P = 2.75E-4) and "A/A" genotype carriers were with even higher SLE risk (OR = 1.464 95% CI 1.259 to 1.702, P = 7.48E-7). When combined with another tag SNP rs8192772, we identified haplotype "rs8192772-rs2480256/TA" over presented in SLE patients (OR 1.407, 95% CI 1.182 to 1.675, P = 0.0001) and haplotype "TG" over presented in the controls (OR 0.771, 95% CI 0.667 to 0.890, P = 0.0004). The gene transcription quantitation analysis further proved the dominant effect of rs2480256 as the "A/A" genotype showed highest transcription. CONCLUSIONS: Our results suggest the involvement of CYP2E1 as a susceptibility gene for SLE in the Chinese population.

Genetic factors contribute to patient-specific warfarin dose for Han Chinese.

BACKGROUND: Warfarin is a commonly prescribed anticoagulant drug for the prevention of thromboses. To address the association of genetic factors and warfarin dosage for ethnic Han Chinese, we genotyped six candidate genes involved in the warfarin interactive pathway with focus on SNPs with reported association with warfarin dose. METHODS: We recruited a study population consisted of 318 patients receiving warfarin treatment and 995 healthy controls. PCR and direct sequencing were used to identify the sequence polymorphisms. RESULTS: In our study population, SNP rs1799853 of CYP2C9, rs1687390 of ORM1-2, and rs2069919 of PROC showed no variation. SNPs rs12714145 of GGCX and rs1799809 of PROC showed no significant correlation with warfarin dose. The associations of SNPs rs9934438 and rs9923231 of VKORC1, the 3 (rs1057910) and C(-65) (rs9332127) alleles of CYP2C9, and SNP rs4653436 of EPHXI with the dose of warfarin were significant. CONCLUSION: A multiple regression model based on the genetic polymorphisms of VKORC1, CYP2C9, EPHX1 and the non-genetic factors of age and body weight can explain 40.2% of the variance in warfarin dose in Han Chinese patients. Translation of this knowledge into clinical guidelines for warfarin prescription may improve the safety and efficacy of warfarin treatment among Han Chinese.

Effect of CKBM on prostate cancer cell growth in vitro and in vivo.

Prostate carcinoma and metastasis are common among male subjects worldwide. CKBM is a drug product targeting prostate cancer in multiple ways. Prostate cancer cell lines PC3 and DU145 were treated with CKBM. The effect of CKBM on the cell's viability, cell cycle, adhesive and invasive properties and its growth in an animal model were assessed. Results indicated that CKBM inhibited PC3 and DU145 cell growth in vitro at IC(50 )values 3.923 and 4.697% respectively, and it brought about cell cycle arrest at G2/M phase. CKBM also attenuated DU145 cells to invade and adhere to extracellular matrices including Matrigel, laminin, fibronectin and collagen IV. Moreover, PC3 tumor xenograft growth was inhibited by over 60% after 28-day of 0.2, 0.4 or 0.8 ml/day CKBM treatment. The present study indicates that CKBM is effective against prostate cancer cell growth in vitro and in vivo. Further studies are required to elucidate its mechanism of action.

Fangia hongkongensis gen. nov., sp. nov., a novel gammaproteobacterium of the order Thiotrichales isolated from coastal seawater of Hong Kong.

A Gram-negative, coccobacillus-shaped, aerobic bacterium, designated strain UST040201-002T, was isolated in February 2004 from seawater at the outlet of a sandfilter in Port Shelter, Hong Kong SAR, China. This strain possessed ubiquinone-8; its 16S rRNA gene sequence shared only 91% similarity with the sequence from Caedibacter taeniospiralis and 89-90% similarity with sequences from Francisella tularensis, Francisella novicida, Francisella philomiragia and Wolbachia persica. 16S rRNA gene sequence analysis showed that the strain formed a distinct clade with C. taeniospiralis. This subcluster formed a tight coherent group with members of the family Francisellaceae and W. persica. Combined phylogenetic and physiological data suggest that strain UST040201-002T represents a novel genus and species within the order Tauhiotrichales. The name Fangia hongkongensis gen. nov., sp. nov. is proposed; the type strain is UST040201-002T (=JCM 14605T=NRRL B-41860T).

Microsomal glutathione S-transferase gene polymorphisms and colorectal cancer risk in a Han Chinese population.

BACKGROUND AND AIMS: Glutathione S-transferases (GSTs) are phase II detoxification enzymes. Human GSTs have been classified into cytosolic, mitochondrial, and microsomal families. Several studies reported the association of colorectal cancer (CRC) risk with the genetic polymorphisms of cytosolic GSTs. The microsomal GSTs are structurally distinct but functionally similar to cytosolic GSTs; their association with CRC has not been reported. In this report, we summarized the result of a case-control study aimed at investigating the association of MGST1 gene locus polymorphisms with CRC risk among Han Chinese. PATIENT/METHODS: Three hundred and seventy-two healthy controls and 238 sporadic CRC patients participated in this study. DNA resequencing was conducted for the 3.4 kb genomic DNA region containing the promoter, exons, exon-intron junctions, and the 5' and 3' untranslated regions. RESULTS: We detected 13 single nucleotide polymorphisms (SNPs) including four novel SNPs not reported in database/literature. The gene shows a much higher nucleotide diversity than most human genes. The linkage and recombination analysis revealed 24 common haplotypes (13% > or = freq > or = 1%) and identified extensive intragenic recombination throughout the MGST1 locus (R = 81.8). Significant CRC association (P < or = 0.005) was not detected for each individual SNP. However, SNPs 102G>A and 16416G>A reached a marginal level of statistical significance with P values of 0.016 and 0.078, respectively. A combined genotype analysis detected a statistically significant CRC association for individuals carrying 102G>A/16416G>A (GG/GG) genotype (adjusted OR, 1.682; 95% confidence interval (CI), 1.177-2.404; P = 0.004). Consistent with the results of genotype analysis, the GG haplotype (102G>A/16416G>A) with two risk alleles was associated with a significantly higher CRC risk comparing with the haplotypes with one or no risk allele (adjusted OR 1.744; 95% CI 1.309-2.322; P = 0.0001). CONCLUSION: The results suggest that MGST1 polymorphisms may contribute to CRC risk among Han Chinese.

The association of CYP2C9 gene polymorphisms with colorectal carcinoma in Han Chinese.

BACKGROUND: Cytochrome P450 (CYP) 2C9 is an important enzyme involved in xenobiotics metabolism. This study investigated the association of CYP2C9 gene coding region polymorphisms with colorectal cancer (CRC) in Chinese Han population. METHODS: Four hundred and eighty-three healthy controls and 286 sporadic CRC patients participated in this study. Direct sequencing was used to identify the sequence polymorphisms. RESULTS: We detected the significant association of 2 coding region SNPs, rs1057910 and rs1057911, of CYP2C9 with the risk of developing sporadic CRC for Han Chinese. These 2 SNPs showed a strong linkage disequilibrium (LD) (r(2)=0.97, D'=0.985). Significantly different minor allele frequencies were found for SNPs rs1057910 and rs1057911 between the cases (7% and 7.2%, respectively) and controls (3% and 2.9%, respectively) with adjusted P=0.0004 and 0.0002, respectively. Individuals heterozygous for rs1057910A/C or rs1057911A/T showed 2.589-fold (95% CI: 1.549-4.330) or 2.770-fold (95% CI 1.653-4.643) increased risk of developing sporadic CRC. We did not detect any homozygote minor allele carrier for either rs1057910 or rs1057911 in our study population. The CRC association appeared to be more evident for individuals over age 50 y, for men, and for rectum cancer site. CONCLUSION: There is an association of CYP2C9 coding region polymorphisms with the risk of developing CRC in Han Chinese after genotyping cases and controls recruited from different locations in China.

Shewanella irciniae sp. nov., a novel member of the family Shewanellaceae, isolated from the marine sponge Ircinia dendroides in the Bay of Villefranche, Mediterranean Sea.

Strain UST040317-058(T), comprising non-pigmented, rod-shaped, facultatively anaerobic, Gram-negative cells that are motile by means of single polar flagella, was isolated from the surface of a marine sponge (Ircinia dendroides) collected from the Mediterranean Sea. Comparative 16S rRNA gene sequence-based phylogenetic analysis placed the strain in a separate cluster with the recognized bacterium Shewanella algae IAM 14159(T), with which it showed a sequence similarity of 95.0 %. The sequence similarity between strain UST040317-058(T) and its other (six) closest relatives ranged from 91.6 to 93.8 %. Strain UST040317-058(T) showed oxidase, catalase and gelatinase activities. The typical respiratory quinones for shewanellas, menaquinone MK-7 and ubiquinones Q-7 and Q-8, were also detected. The predominant fatty acids in strain UST040317-058(T) were i15 : 0, 16 : 0, 17 : 1omega8c and summed feature 3 (comprising i15 : 0 2-OH and/or 16 : 1omega7c), altogether representing 56.9 % of the total. The DNA G+C content was 39.9 mol%. The strain could be differentiated from other Shewanella species by its inability to reduce nitrate or produce H(2)S and by 10-22 additional phenotypic characteristics. On the basis of the phylogenetic and phenotypic data presented in this study, strain UST040317-058(T) represents a novel species in the genus Shewanella, for which the name Shewanella irciniae sp. nov. is proposed. The type strain is UST040317-058(T) (=JCM 13528(T)=NRRL B-41466(T)).

Marinomonas ostreistagni sp. nov., isolated from a pearl-oyster culture pond in Sanya, Hainan Province, China.

A Gram-negative, aerobic, halophilic, neutrophilic, rod-shaped, non-pigmented, polar-flagellated bacterium, UST010306-043(T), was isolated from a pearl-oyster culture pond in Sanya, Hainan Province, China in January 2001. This marine bacterium had an optimum temperature for growth of between 33 and 37 degrees C. On the basis of 16S rRNA gene sequence analysis, the strain was closely related to Marinomonas aquimarina and Marinomonas communis, with 97.5-97.7 and 97.1 % sequence similarity, respectively. Levels of DNA-DNA relatedness to the type strains of these species were well below 70 %. Analyses of phylogenetic, phenotypic and chemotaxomonic characteristics showed that strain UST010306-043(T) was distinct from currently established Marinomonas species. A novel species with the name Marinomonas ostreistagni sp. nov. is proposed to accommodate this bacterium, with strain UST010306-043(T) (=JCM 13672(T)=NRRL B-41433(T)) as the type strain.

Lishizhenia caseinilytica gen. nov., sp. nov., a marine bacterium of the phylum Bacteroidetes.

A light-orange, aerobic bacterium, strain UST040201-001(T), that degrades casein, gelatin and Tween 20, was isolated in February 2004 from a sand-filtered seawater sample from Port Shelter, Hong Kong SAR, China. The strain possessed menaquinone-6 and its 16S rRNA gene sequence shared only 90.1 % similarity with that of Brumimicrobium glaciale IC156(T). Phylogenetic analysis showed that UST040201-001(T) formed a distinct lineage within the family Cryomorphaceae. Its ecophysiological and biochemical characteristics suggest that this strain represents a novel genus and species within the phylum Bacteroidetes. The name Lishizhenia caseinilytica gen. nov., sp. nov. is proposed. The type strain of Lishizhenia caseinilytica is UST040201-001(T) (=NRRL B-41434(T)=JCM 13821(T)).

Gillisia myxillae sp. nov., a novel member of the family Flavobacteriaceae, isolated from the marine sponge Myxilla incrustans.

A yellow-pigmented, Gram-negative, rod-shaped, strictly aerobic bacterium (strain UST050418-085(T)) was isolated from the surface of a marine sponge, Myxilla incrustans, at Friday Harbor, WA, USA. The DNA G+C content of this strain was 34.6 mol%. The predominant fatty acids were i15 : 0, a15 : 0, i15 : 1, i16 : 0, i17 : 0 3-OH, 17 : 0 2-OH and summed feature 3, comprising i15 : 0 2-OH and/or 16 : 1omega7c (altogether representing 69.0 % of the total fatty acids). MK-6 was the only respiratory quinone detected. Phylogenetic analysis based on 16S rRNA gene sequences indicated that the closest relatives of UST050418-085(T) were members of the genus Gillisia, with sequence similarities of 93.2-96.6 %. Strain UST050418-085(T) differed from its closest relatives by 11 to 18 phenotypic traits. Molecular evidence and phenotypic characteristics suggest that strain UST050418-085(T) represents a novel species within the genus Gillisia. The name Gillisia myxillae sp. nov. is proposed, with UST050418-085(T) (=JCM 13564(T)=NRRL B-41416(T)) [corrected] as the type strain.

An ATP-binding cassette transporter related to yeast vacuolar ScYCF1 is important for Cd sequestration in Chlamydomonas reinhardtii.

We generated a Cd-sensitive insertional mutant, Cds18, in Chlamydomonas reinhardtii and elucidated the deletion of a 10 kb fragment containing the promoter and a portion of the coding region for CrMRP2 gene that silenced the transcription of CrMRP2 in mutant Cds18. The association between CrMRP2 and Cd sensitivity was confirmed by complementing mutant Cds18 with a cloned genomic DNA fragment containing the promoter and complete coding sequence for CrMRP2. The genomic region and the full-length cDNA for CrMRP2 were cloned and sequenced. Computer searches detected the significant resemblance of CrMRP2 with HsMRP1, AtMRP3 and ScYCF1, in Homo sapiens, Arabidopsis thaliana and Saccharomyces cerevisiae, respectively. All are members of the multidrug resistance-associated protein (MRP)/cystic fibrosis transmembrane conductance regulator (CFTR) subfamily of ATP-binding cassette (ABC) transporters. When the cDNA of CrMRP2 was cloned into the yeast expression vector pEGKT and transformed into the yeast mutant strain DTY168 lacking ScYCF1, it restored the function of ScYCF1, a yeast vacuolar glutathione (GSH)-conjugate ABC transporter. A putative vacuolar-targeting motif (T/I/K)LP(L/K/I) was detected in the N-terminal part of CrMRP2. In wild-type C. reinhardtii, CrMRP2 transcription was significantly up-regulated upon Cd treatment. Comparing with mutant Cds18, the wild-type algal cells accumulated and sequestered more Cd in the stable high molecular weight (HMW) phytochelatin (PC)-Cd complex; the labile low molecular weight (LMW) PC-Cd complex was detected in mutant Cds18 at an earlier stage of Cd treatment. This study demonstrated the expression of CrMRP2 in C. reinhardtii and implicated its function in the formation/accumulation of stable HMW PC-Cd complex.

Description of Fabibacter halotolerans gen. nov., sp. nov. and Roseivirga spongicola sp. nov., and reclassification of [Marinicola] seohaensis as Roseivirga seohaensis comb. nov.

Bacterial strains UST030701-097T and UST030701-084T were isolated from a marine sponge in the Bahamas. Both strains were pink-pigmented, Gram-negative, strictly aerobic and chemo-organotrophic. Cells of strain UST030701-097T were short, curved rods with fast-gliding motility, whereas those of strain UST030701-084T were straight rods with a less rapid gliding motion. The two strains had MK-7 as the major respiratory quinone and did not produce flexirubin-type pigments. The DNA G+C contents of strains UST030701-097T and UST030701-084T were 42.5 and 43.7 mol%, respectively. Phylogenetic analysis based on 16S rRNA gene sequences indicated that the two strains belonged to the family 'Flexibacteraceae' of the phylum Bacteroidetes. 16S rRNA gene sequence similarity between strains UST030701-097T and UST030701-084T was 95.0 %; their closest relative was [Marinicola] seohaensis, with 93.3 % and 96.0 % sequence similarity, respectively. Phylogenetic tree topology indicated that the two strains belonged to the same lineage, but were on separate branches. Whilst strain UST030701-084T and [Marinicola] seohaensis were found on one branch, strain UST030701-097T was in another branch that had no species with validly published names. Based on the polyphasic taxonomic data obtained in the present study, we propose that strain UST030701-097T represents a novel genus and that strain UST030701-084T represents a novel species in the phylum Bacteroidetes. The genus Fabibacter gen. nov. is proposed, with strain UST030701-097T (=NRRL B-41220T=JCM 13334T) as the type strain of the type species, Fabibacter halotolerans sp. nov. Strain UST030701-084T (=NRRL B-41219T=JCM 13337T) is proposed as the type strain of Roseivirga spongicola sp. nov. In an earlier study, it was suggested that the genus Marinicola is a later heterotypic synonym of the genus Roseivirga. However, a formal proposal to reclassify [Marinicola] seohaensis, the only member of the genus Marinicola, has not yet been made. The results of phylogenetic analyses in this study support the reclassification of [Marinicola] seohaensis as Roseivirga seohaensis comb. nov.

Stenothermobacter spongiae gen. nov., sp. nov., a novel member of the family Flavobacteriaceae isolated from a marine sponge in the Bahamas, and emended description of Nonlabens tegetincola.

A bacterial strain, UST030701-156T, was isolated from a marine sponge in the Bahamas. Strain UST030701-156T was orange-pigmented, Gram-negative, rod-shaped with tapered ends, slowly motile by gliding and strictly aerobic. The predominant fatty acids were a15 : 0, i15 : 0, i15 : 0 3-OH, i17 : 0 3-OH, i17 : 1omega9c and summed feature 3, comprising i15 : 0 2-OH and/or 16 : 1omega7c. MK-6 was the only respiratory quinone. Flexirubin-type pigments were not produced. Phylogenetic analysis based on 16S rRNA gene sequences placed UST030701-156T within a distinct lineage in the family Flavobacteriaceae, with 93.3 % sequence similarity to the nearest neighbour, Nonlabens tegetincola. The DNA G+C content of UST030701-156T was 41.0 mol% and was much higher than that of N. tegetincola (33.6 mol%). Strain UST030701-156T can be distinguished from other members of the Flavobacteriaceae by means of a number of chemotaxonomic and phenotypic characteristics. It is proposed, therefore, that UST030701-156T represents a novel taxon designated Stenothermobacter spongiae gen. nov., sp. nov. The type strain is UST030701-156T (= NRRL B-41138T = JCM 13191T). Carbon-source utilization by N. tegetincola was re-examined and an emended description is therefore included.

Winogradskyella poriferorum sp. nov., a novel member of the family Flavobacteriaceae isolated from a sponge in the Bahamas.

A Gram-negative, rod-shaped bacterium (designated strain UST030701-295(T)) with fast gliding motility was isolated from the surface of the sponge Lissodendoryx isodictyalis in the Bahamas. Colonies of UST030701-295(T) were yellow in colour, 2-4 mm in diameter, convex with a smooth surface and entire margins. UST030701-295(T) was heterotrophic, strictly aerobic and required NaCl for growth (1.0-4.0%). Growth was observed at pH 6.0-10.0 and at 12-44 degrees C. Phylogenetic analysis of the 16S rRNA gene sequence placed UST030701-295(T) within the genus Winogradskyella of the family Flavobacteriaceae, sharing 94.7-95.8% similarity with the three recognized members of the genus. The G+C content of the DNA was 32.8 mol% and the predominant fatty acids were iso-C(15:1), iso-C(15:0), iso-C(15:0) 2-OH, iso-C(15:0) 3-OH, iso-C(16:0) 3-OH, C(16:1)omega7 and iso-C(17:0) 3-OH (together representing 75.4% of the total); these data supported the affiliation of UST030701-295(T) to the genus Winogradskyella. UST030701-295(T) differed from the three recognized species of Winogradskyella in 7-17 traits. Molecular evidence together with phenotypic characteristics suggests that UST030701-295(T) represents a novel species within the genus Winogradskyella, for which the name Winogradskyella poriferorum sp. nov. is proposed. The type strain is UST030701-295(T) (=NRRL B-41101(T)=JCM 12885(T)).

Owenweeksia hongkongensis gen. nov., sp. nov., a novel marine bacterium of the phylum 'Bacteroidetes'.

An aerobic, Gram-negative, non-fermentative, rod-shaped, motile, orange-pigmented bacterium, UST20020801(T), was isolated from sea-water samples collected from Port Shelter, Hong Kong, S.A.R., China, in August 2002. The full 16S rRNA gene sequence of this strain shared only 87.5 % similarity with its nearest relative, Crocinitomix catalasitica, a species of the family Cryomorphaceae. However, strain UST20020801(T) possessed menaquinone-6, a major respiratory quinone of members of the family Flavobacteriaceae. This strain contains unique fatty acids such as i15 : 1G, i17 : 1omega9c, 2-OH 15 : 0, 15 : 1omega6c and three unknown fatty acids of equivalent chain-length of 11.543, 13.565 and 16.582. Further analysis of its ecophysiology and biochemistry suggests that this strain represents a new genus in the phylum 'Bacteroidetes'. The name Owenweeksia hongkongensis gen. nov., sp. nov. is proposed. The type strain is UST20020801(T) (=NRRL B-23963(T) = JCM 12287(T)).

Loktanella hongkongensis sp. nov., a novel member of the alpha-Proteobacteria originating from marine biofilms in Hong Kong waters.

A Gram-negative, non-motile, non-spore-forming, short rod-shaped bacterium (UST950701-009P(T)) was isolated from a marine biofilm in Hong Kong waters. Colonies are pink in colour, convex with a smooth surface and entire edge. Brown diffusible pigment is produced. Whitish colonies, with otherwise identical morphology, emerge from every culture upon ageing. The white colonies can be maintained as separate cultures (UST950701-009W) without turning pink. UST950701-009P(T) and UST950701-009W have identical 16S rRNA gene sequences and similar G+C (65.9-66.2 mol%) and fatty acid (86.22-88.52 % 18 : 1omega7c) contents. Phylogenetic analysis of the 16S rRNA gene sequence places UST950701-009P(T) within the Rhodobacter group of the alpha-subclass of the Proteobacteria. The nearest neighbours belong to the genus Loktanella, with similarity values ranging from 94.5 to 95.5 %. Data on G+C and fatty acid contents support the affiliation to the genus Loktanella. UST950701-009P(T) and -009W are heterotrophic, strictly aerobic and require NaCl for growth (2.0-14.0 %). Both grow in pH 5.0-10.0 and at 8-44 degrees C. Both are positive in oxidase, catalase and beta-galactosidase tests, but they differ in the pattern of carbohydrate oxidation and assimilation. Molecular evidence together with phenotypic characteristics shows that UST950701-009P(T) constitutes a novel species within the genus Loktanella. The name Loktanella hongkongensis sp. nov. is proposed; the type strain is UST950701-009P(T) (=NRRL B-41039(T)=JCM 12479(T)) and a morphovar is UST950701-009W (=NRRL B-41040=JCM 12480).

Species diversity and distribution for phytoplankton of the Pearl River estuary during rainy and dry seasons.

Based on data collected at 31 stations and 1 continuous station in the Pearl River estuary during cruises of July 1999 (rainy season) and January 2001 (dry season), this study examined taxonomic composition, abundance, and spatial distribution of phytoplankton. Results indicated 130 species of phytoplankton in the samples from the rainy season, and 132 species in the dry season. Among them, in the rainy season, 82 species of diatom, 39 fresh-water and half-fresh-water species and 41 species of red tide organisms were found. Within these, there were 54 tropical and sub-tropical species, 47 cosmopolitan species and 17 temperate species. The abundance of phytoplankton in the rainy season was higher than that of the dry season, with an average of 6.3 x 10(5) cells x L(-1) and 1.4 x 10(5) cells x L(-1), respectively. Diversity index (H') and evenness (J) were 2.47 and 0.57 in the rainy season, and 2.01 and 0.54 in the dry season. The dominant phytoplankton species in the rainy season was Skeletonema costatum with an average of 2.8 x 10(5) cells x L(-1) and 45.0% of the total phytoplankton abundance. In the dry season, Eucampia zoodiacus became the key dominant species (5.9 x 10(4) cells x L(-1)) when it was 43.47% of the total phytoplankton abundance. Distribution of the dominant species varied with salinity of sea-water, and their amounts correlated negatively with nutrients and zooplankton.

High yield production of salidroside in the suspension culture of Rhodiola sachalinensis.

Salidroside has been identified as the most potent ingredient of the Chinese medicine herb, Rhodiola sachalinensis. Since the natural supply of this herb is rapidly decreasing, we established a compact callus aggregate (CCA) strain and culturing system for high yield salidroside production. Several callus strains induced from the explants originated from root, stem, leaf and cotyledon of R. sachalinensis were established and screened for rapid growth rate, high salidroside content and easy propagation in suspension culture condition. The CCA strain was established from a callus strain initiated from the cotyledon. The kinetics of dry weight accumulation and cellular salidroside content in various culture conditions for the strain was determined. For high salidroside production, the optimal inoculum amount was 10% and the optimal concentration for 6-benzylaminopurine and indole-3-butyric acid added in the liquid medium was 5 and 2.5 mg l-1, respectively. The acidic culture medium and a faster shaking speed favored the salidroside accumulation. The addition of 2,4-D, in the liquid MS medium and the utilization of L-tyrosol for chemical feeding enhanced salidroside production. Using a proper combination of culture condition and treatment, salidroside accumulation could reach 57.72 mg g-1 dry weight, that was 5-10-fold higher than that detected in field-grown plants. The corresponding salidroside yield was 555.13 mg l-1, a level suitable for cost effective commercial production to compensate the natural resource shortage of R. sachalinensis.