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At least 829 records · Page 46Linked to original sources
PubMed2003

Effects of storage on efficacy of red cell transfusion: when is it not safe?

OBJECTIVE: To review the literature on red blood cell storage and its relationship to the efficacy of transfusion. RESULTS: Well-documented changes occur to the red blood cell product during ex vivo storage. These changes include a reduction in red blood cell deformability, altered red blood cell adhesiveness and aggregability, and a reduction in 2,3-diphosphoglycerate and ATP. Bioactive compounds with proinflammatory effects also accumulate in the storage medium. These changes reduce posttransfusion viability of red blood cells. The clinical effects beyond posttransfusion viability are uncertain, but a growing body of evidence suggests that the storage lesion may reduce tissue oxygen availability, have proinflammatory and immunomodulatory effects, and influence morbidity and mortality. There are no published randomized, control trials examining the effect of storage duration on morbidity and mortality. Leukoreduction improves the quality of stored red blood cell products and in some studies has been shown to reduce morbidity and mortality. CONCLUSION: Although storage duration influences the quality of red blood cell product, there is currently insufficient evidence to advocate shorter storage periods for red blood cell products.

Anemia↗
PubMed2004

Vitamin A, retinoids and carotenoids as chemopreventive agents for prostate cancer.

PURPOSE: Evidence is examined for the use of vitamin A, retinoids and carotenoids as chemopreventive agents for prostate cancer. MATERIALS AND METHODS: Studies in in vitro and animal experimental models as well as in human observational (epidemiologic) and experimental studies are reviewed. RESULTS: There is little evidence that dietary vitamin A is associated with prostate cancer risk and, thus, it is unlikely that vitamin A or retinyl palmitate, the form most often used in dietary supplements, would be useful as chemoprevention agents. Several pharmaceutical formulations of retinoids show cancer prevention properties in animal experimental models but their high toxicity makes them unlikely candidates for cancer prevention. There is also currently no evidence that dietary carotenoids (except for lycopene and possibly other bioactive compounds found in tomato products) will be useful for prostate cancer prevention. Epidemiological and experimental studies show no association of beta-carotene with prostate cancer risk. There is inconsistent though intriguing evidence from epidemiological studies that tomato products and/or lycopene is associated with reduced prostate cancer risk. However, animal experimental studies of lycopene and prostate cancer are not strongly supportive, and the results of human experimental studies are not interpretable due to poor design. CONCLUSIONS: There is currently no evidence that vitamin A, synthetic retinoids or carotenoids can be used as prostate cancer chemopreventive agents. Experimental studies are needed to determine whether lycopene or other compounds in tomatoes have chemopreventive properties.

Animals↗
PubMed2026

Investigating the mechanisms linking vitamin D to coronary artery disease: A mediating proteomics Mendelian randomisation study.

Coronary artery disease (CAD) is a leading cause of mortality and morbidity globally, with its elevated rates of disability and death posing a significant public health concern. Vitamin D is a crucial bioactive compound involved in numerous physiological processes and has garnered considerable interest due to its potential health benefits. The association between vitamin D and CAD has been a prominent focus of scholarly investigation. However, there remains considerable debate regarding whether vitamin D confers protective effects against CAD, and the underlying mechanisms by which vitamin D influences CAD remain inadequately understood. Mendelian randomization analysis was performed using large-scale genome-wide association study data to examine the causal relationship between serum 25-hydroxyvitamin D (25(OH)D) levels and CAD. Plasma proteomics data were subsequently employed for mediation analysis, followed by enrichment analysis to identify intermediary metabolic or signaling pathways through which serum 25(OH)D may mediate the onset and progression of CAD. The Mendelian randomization analysis indicated that higher serum 25(OH)D levels were associated with a reduced risk of CAD (odds ratio [95% confidence interval]: 0.799 [0.643-0.993], P = .043). No evidence of pleiotropy (P = .949) or heterogeneity (P = .630) was observed in the results. The protein-mediated analysis identified 19 plasma proteins, including Serine/threonine-protein kinase TBK1, membrane associating domain domain-containing protein 2, and interleukin-17D, as key mediators through which reduced vitamin D levels contribute to the development of CAD. The mediation effects ranged from 4.85 to 34.49%. Following the identification of these 19 mediating proteins, 59 intermediary pathways were further pinpointed through which serum vitamin D influences CAD risk. Increased levels of 25(OH)D may reduce the risk of CAD. Further, plasma proteomics-mediated analyses have uncovered potential mechanisms through which 25(OH)D influences the development of CAD, offering a detailed framework for understanding the relationship between vitamin D deficiency and CAD progression. This provides novel evidence to support the recommendation of appropriate vitamin D supplementation as part of lifestyle guidance for CAD patients.

Coronary Artery Disease↗
PubMed2001

The taxonomy of Streptomyces and related genera.

The streptomycetes, producers of more than half of the 10,000 documented bioactive compounds, have offered over 50 years of interest to industry and academia. Despite this, their taxonomy remains somewhat confused and the definition of species is unresolved due to the variety of morphological, cultural, physiological and biochemical characteristics that are observed at both the inter- and the intraspecies level. This review addresses the current status of streptomycete taxonomy, highlighting the value of a polyphasic approach that utilizes genotypic and phenotypic traits for the delimitation of species within the genus.

Base Sequence↗
PubMed2005

Dragon Plant Biology Explorer. A text-mining tool for integrating associations between genetic and biochemical entities with genome annotation and biochemical terms lists.

We introduce a tool for text mining, Dragon Plant Biology Explorer (DPBE) that integrates information on Arabidopsis (Arabidopsis thaliana) genes with their functions, based on gene ontologies and biochemical entity vocabularies, and presents the associations as interactive networks. The associations are based on (1) user-provided PubMed abstracts; (2) a list of Arabidopsis genes compiled by The Arabidopsis Information Resource; (3) user-defined combinations of four vocabulary lists based on the ones developed by the general, plant, and Arabidopsis GO consortia; and (4) three lists developed here based on metabolic pathways, enzymes, and metabolites derived from AraCyc, BRENDA, and other metabolism databases. We demonstrate how various combinations can be applied to fields of (1) gene function and gene interaction analyses, (2) plant development, (3) biochemistry and metabolism, and (4) pharmacology of bioactive compounds. Furthermore, we show the suitability of DPBE for systems approaches by integration with "omics" platform outputs. Using a list of abiotic stress-related genes identified by microarray experiments, we show how this tool can be used to rapidly build an information base on the previously reported relationships. This tool complements the existing biological resources for systems biology by identifying potentially novel associations using text analysis between cellular entities based on genome annotation terms. Thus, it allows researchers to efficiently summarize existing information for a group of genes or pathways, so as to make better informed choices for designing validation experiments. Last, DPBE can be helpful for beginning researchers and graduate students to summarize vast information in an unfamiliar area. DPBE is freely available for academic and nonprofit users at http://research.i2r.a-star.edu.sg/DRAGON/ME2/.

Arabidopsis↗
PubMed2005

Capillary feeding of specific dsRNA induces silencing of the isac gene in nymphal Ixodes scapularis ticks.

Ixodes scapularis transmits several pathogens including Borrelia burgdorferi. Bioactive compounds in tick saliva support tick feeding and influence pathogen transmission to the mammalian host. These studies utilized oral delivery of dsRNA to silence an anticomplement gene (isac) in I. scapularis nymphs. Silencing of isac significantly reduced fed-tick weight compared to delivery of control lacZ dsRNA, and immunoblots specific for FlaB protein indicated a reduction in spirochete load in isac-silenced infected nymphs. SDS-PAGE demonstrated that isac gene silencing affected expression of a number of salivary and non-salivary gland proteins in ticks. Finally, multiple isac cDNA homologues were cloned, and these may represent a new gene family coexpressed during tick feeding. This work presents a novel oral delivery approach for specific gene silencing in I. scapularis nymphs and characterizes the effect of isac on blood-feeding in an attempt to block transmission of B. burgdorferi.

Animals↗
PubMed2006

Mycelium cultivation, chemical composition and antitumour activity of a Tolypocladium sp. fungus isolated from wild Cordyceps sinensis.

AIMS: To examine and illustrate the morphological characteristics and growth kinetics of Cs-HK1, a Tolypocladium fungus, isolated from wild Cordyceps sinensis in solid and liquid cultures, and the major chemical constituents and antitumour effects of Cs-HK1 mycelium. METHODS AND RESULTS: The Cs-HK1 fungus was isolated from the fruiting body of a wild C. sinensis and identified as a Tolypocladium sp. fungus. It grew rapidly at 22-25 degrees C on a liquid medium containing glucose, yeast extract, peptone and major inorganic salts, with a specific growth rate of 1.1 day(-1), reaching a cell density of 23.0 g dw l(-1) in 7-9 days. Exopolysaccharides accumulated in the liquid culture to about 0.3 g l(-1) glucose equivalent. In comparison with natural C. sinensis, the fungal mycelium had similar contents of protein (11.7-microg) and carbohydrate (654.6-microg) but much higher contents of polysaccharide (244.2 mg vs 129.5 mg), adenosine (1116.8-microg vs 264.6 microg) and cordycepin (65.7 microg vs 20.8 microg) (per gram dry weight). Cyclosporin A, an antibiotic commonly produced by Tolypocladium sp., was also detected from the mycelium extract. The hot water extract of mycelium showed low cytotoxic effect on B16 melanoma cells in culture (about 25% inhibition) but significant antitumour effect in animal tests, causing 50% inhibition of B16 cell-induced tumour growth in mice. CONCLUSIONS: The Tolypocladium sp. fungus, Cs-HK1, can be easily cultivated by liquid fermentation. The mycelium biomass contained the major bioactive compounds of C. sinensis, and the mycelium extract had significant antitumour activity. SIGNIFICANCE AND IMPACT OF THE STUDY: The Cs-HK1 fungus may be a new and promising medicinal fungus and an effective and economical substitute of the wild C. sinensis for health care.

Animals↗
PubMed1997

Cytochrome P450 2D6 and glutathione S-transferase genotype in sudden infant death syndrome.

OBJECTIVES: The risk of sudden infant death syndrome (SIDS) has been linked with xenobiotic exposures, race and inheritance. Because cytochrome P450 2D6 (CYP2D6) and glutathione S-transferases (GSTM1 and GSTT1) are genetically regulated, polymorphically distributed, and responsible for detoxification of many centrally acting exogenous and endogenous bioactive compounds, our objective was to determine whether the prevalences of deficiencies in CYP2D6, GSTM1, and GSTT1 differ in SIDS victims compared to healthy controls. METHODS: CYP2D6 mutations (deletion, A, B, and T alleles) and GSTM1 and GSTT1 null genotypes were assessed in DNA from 50 SIDS victims. CYP2D6 phenotype, assigned using dextromethorphan urinary ratios, was assessed in 25 unrelated parents of SIDS victims. RESULTS: The CYP2D6B mutation was the only mutant CYP2D6 allele found in SIDS victims, present in 26.2% of patients (11/42) and 13.1% (11/84) of alleles. Adjusting for race, the prevalence of wild-type CYP2D6 alleles and of homozygous wild-type CYP2D6 phenotype was not different in SIDS victims compared to controls (P = 0.585 and 0.224, respectively). Among the 25 parents of SIDS victims, all subjects were extensive metabolizers, a prevalence not different from controls (P = 0.243). The prevalence of the null genotype for GSTM1, GSTT1 and double-null for GSTM1 and GSTT1 was 33.3%, 21.4% and 9.5%, respectively, among SIDS victims, and was not different than controls (P = 0.61, 0.1, 0.28, respectively). The combination of CYP2D6 homozygous wild-type genotype and the null genotype for GSTM1, GSTT1, or both GSTM1 + GSTT1 also did not differ in SIDS victims and controls. CONCLUSIONS: The frequencies of CYP2D6 mutant genotypes and the null genotypes for GSTM1 and GSTT1 were not different among SIDS victims compared to normal controls, and thus these polymorphisms are unlikely to identify families with a high risk of SIDS.

Cytochrome P-450 CYP2D6↗
PubMed2006

Mixed-type noncompetitive inhibition of anthrax lethal factor protease by aminoglycosides.

We report a detailed kinetic investigation of the aminoglycosides neomycin B and neamine as inhibitors of the lethal factor protease from Bacillus anthracis. Both inhibitors display a mixed-type, noncompetitive kinetic pattern, which suggests the existence of multiple enzyme-inhibitor binding sites or the involvement of multiple structural binding modes at the same site. Quantitative analysis of the ionic strength effects by using the Debye-Hückel model revealed that the average interionic distance at the point of enzyme-inhibitor attachment is likely to be extremely short, which suggests specific, rather than nonspecific, binding. Only one ion pair seems to be involved in the binding process, which suggests the presence of a single binding site. Combining the results of our substrate competition studies with the ionic strength effects on the apparent inhibition constant, we propose that aminoglycoside inhibitors, such as neomycin B, bind to the lethal factor protease from B. anthracis in two different structural orientations. These results have important implications for the rational design of lethal factor protease inhibitors as possible therapeutic agents against anthrax. The strategies and methods we describe are general and can be employed to investigate in depth the mechanism of inhibition by other bioactive compounds.

Aminoglycosides↗
PubMed2002

The sphingomyelin-signaling pathway in skeletal muscles and its role in regulation of glucose uptake.

Sphingomyelin has been shown to be a source of bioactive compounds. This sphingolipid is located mostly in the outer layer of the plasma membrane and in the membranes of organelles. Sphingomyelin located in the plasma membrane is hydrolyzed into ceramide and phosphorylcholine. Ceramide is the principal second messenger in the sphingomyelin transmembrane signaling pathway. Products of ceramide metabolism, namely, sphingosine, sphingosine-1-phosphate, and ceramide-1-phosphate, also exert broad biological effects. The major effects of ceramide are induction of differentiation, inhibition of proliferation, regulation of inflammatory processes, and induction of apoptosis. There is also convincing evidence that ceramide counteracts insulin-stimulated glucose uptake. Ceramides are also present in skeletal muscles. We investigated ceramide metabolism in different skeletal muscle types of the rat at rest and after prolonged exercise of moderate intensity. Exercise reduced the total content of ceramide fatty acids and changed their composition in each muscle type. These data indicate that the sphingomyelin-signaling pathway functions in skeletal muscles and that its activity is downregulated during prolonged exercise. The content of ceramide in the muscles was inversely related to 2-deoxyglucose uptake by the muscles. This indicates that ceramide may be involved in regulation of glucose uptake by skeletal muscles in vivo.

Animals↗
PubMed2004

Dietary calcium and dairy modulation of adiposity and obesity risk.

Dietary calcium plays a key role in the regulation of energy metabolism and obesity risk. This appears to be mediated primarily by dietary calcium modulation of circulating calcitriol, which in turn regulates adipocyte intracellular calcium ([Ca2+]i). Increased [Ca2+]i stimulates lipogenic gene expression and activity and inhibits lipolysis, resulting in increased adipocyte lipid accumulation. Since calcitriol stimulates adipocyte Ca2+ influx, low calcium diets promote adiposity, while dietary calcium-suppression of calcitriol reduces adiposity. These concepts are confirmed in controlled rodent studies as well as by epidemiological and clinical trial data, all of which confirm protection from obesity with high calcium intakes. Moreover, dairy sources of calcium exert markedly greater effects which are most likely attributable to additional bioactive compounds in dairy which act synergistically with calcium to attenuate adiposity.

Animals↗
PubMed1997

Pharmacological activity of feverfew (Tanacetum parthenium (L.) Schultz-Bip.): assessment by inhibition of human polymorphonuclear leukocyte chemiluminescence in-vitro.

The bioactivity of feverfew (Tanacetum parthenium) leaf extracts has been analysed, by use of a human polymorphonuclear leukocyte (PMNL) bioassay, to assess the relative contributions of solvent extraction and parthenolide content to the biological potency of the extract. Extracts prepared in acetone-ethanol (system 1) contained significantly more parthenolide (mean +/- s.d. 1.3 +/- 0.2% dry leaf weight) than extracts in chloroform-PBS (phosphate-buffered saline; system 2; 0.1 +/- 0.04% dry leaf weight) or PBS alone (system 3; 0.5 +/- 0.1% dry leaf weight). Extract bioactivity, measured as inhibition of phorbol 12-myristate 13-acetate-induced, 5-amino-2,3-dihydro-1,4-phthalazinedione (luminol)-enhanced PMNL, chemiluminescence, followed a similar trend. Extracts inhibited phorbol 12-myristate 13-acetate-induced oxidative burst by amounts which, if solely attributable to parthenolide, indicated parthenolide concentrations for the respective solvent systems of 2.2 +/- 0.6%, 0.2 +/- 0.1% and 0.9 +/- 0.1% dry leaf weight. The mean ratio of parthenolide concentration to the parthenolide equivalent/PMNL-bioactivity value, for acetone-ethanol and PBS extracts were both 1:1.7. Parthenolide, although a key determinant of biological activity for T. parthenium leaf extracts based on the PMNL-bioassay, seems not to be the sole pharmacologically-active constituent. The identical and elevated bioactivity-parthenolide ratios for both organic and aqueons-phase leaf extracts suggest that a proportion of the other bioactive compounds have solubilities similar to that of parthenolide.

Chromatography, High Pressure Liquid↗
PubMed2006

In vitro and in vivo nuclear factor-kappaB inhibitory effects of the cell-penetrating penetratin peptide.

Penetratin is a cationic cell-penetrating peptide that has been frequently used for the intracellular delivery of polar bioactive compounds. Recent studies have just revealed the major role of polyanionic membrane proteoglycans and cholesterol-enriched lipid rafts in the uptake of the peptide. Both proteoglycans and lipid-rafts influence inflammatory processes by binding a wide array of proinflammatory mediators; thus, we decided to analyze the effect of penetratin on in vitro and in vivo inflammatory responses. Our in vitro luciferase gene assays demonstrated that penetratin decreased transcriptional activity of nuclear factor-kappaB (NF-kappaB) in tumor necrosis factor (TNF)-stimulated L929 fibroblasts and lipopolysaccharide-activated RAW 264.7 macrophages. Penetratin also inhibited TNF-induced intercellular adhesion molecule-1 expression in human endothelial HMEC-1 cells. Exogenous heparan sulfate abolished the in vitro NF-kappaB inhibitory effects of the peptide. Uptake experiments showed that penetratin was internalized by all of the above-mentioned cell lines in vitro and rapidly entered the cells of the lung and pancreas in vivo. In an in vivo rat model of acute pancreatitis, a disease induced by elevated activities of stress-responsive transcription factors like NF-kappaB, pretreatment with only 2 mg/kg penetratin attenuated the severity of pancreatic inflammation by interfering with IkappaB degradation and subsequent nuclear import of NF-kappaB, inhibiting the expression of proinflammatory genes and improving the monitored laboratory and histological parameters of pancreatitis and associated oxidative stress.

Amino Acid Sequence↗
PubMed2001

Analysis of sphingosine 1-phosphate, ceramides, and other bioactive sphingolipids by high-performance liquid chromatography-tandem mass spectrometry.

The lipid backbones of sphingolipids and their metabolites are highly bioactive compounds that affect diverse cellular functions. The metabolites that have been most extensively studied with respect to their effects on cell behavior are ceramides, sphingosine (and other sphingoid bases), and sphingosine 1-phosphate. Additionally, there is interest in other naturally occurring species such as lysosphingolipids (sphingosine, phosphorylcholine, and psychosines) and N-methyl (di- and tri-methyl)-sphingosines. In many cases, studies of cell signaling mediated by these compounds have focused on a single category (such as ceramides or sphingosine 1-phosphate) because of the technical difficulty of more comprehensive analyses. One obstacle in such studies is that most of these compounds are metabolically interconvertable, so it is difficult to assign a conclusive relationship. In this article, we describe the analytical methods for extraction, identification, and quantitation of sphingolipids using state-of-the-art tandem mass spectrometry (MS/MS). Precursor ion scans are used to distinguish various species of sphingolipids in crude extracts by their unique molecular decomposition products. Specific headgroup, sphingoid base, and fatty acid chain combinations can be readily determined. Quantitation is achieved by multiple reaction monitoring (MRM) in conjunction with high-pressure liquid chromatography (HPLC). Compared to precursor ion scans alone, MRM experiments yield greater sensitivity and lower limits of detection by monitoring a specific precursor and product ion pair. This sensitivity facilitates detection of dozens of individual molecular species under optimal ion formation and decomposition conditions for each species, eliminating any ambiguity that may arise from differences in the kinetics of dissociation.

Animals↗
PubMed1993

Isolation and diversity of actinomycetes in the chesapeake bay.

Chesapeake Bay was investigated as a source of actinomycetes to screen for production of novel bioactive compounds. The presence of relatively large populations of actinoplanetes (chemotype II/D actinomycetes) in Chesapeake Bay sediment samples indicates that it is an eminently suitable ecosystem from which to isolate actinomycetes for screening programs. Actinomycetes were isolated from sediment samples collected in Chesapeake Bay with an isolation medium containing nalidixic acid, which proved to be more effective than heat pretreatment of samples. Actinomycete counts ranged from a high of 1.4 x 10 to a low of 1.8 x 10 CFU/ml of sediment. Actinomycetes constituted 0.15 to 8.63% of the culturable microbial community. The majority of isolates from the eight stations studied were actinoplanetes (i.e., chemotype II/D), and 249 of these isolates were obtained in a total of 298 actinomycete isolates. Antimicrobial activity profiles indicated that diverse populations of actinoplanetes were present at each station. DNA hybridization studies showed considerable diversity among isolates between stations, but indicated that actinoplanete strains making up populations at nearby stations were more similar to each other than to populations sampled at distant stations. The diversity of actinoplanetes and the ease with which these organisms were isolated from Chesapeake Bay sediments make this a useful source of these actinomycetes.

Journal Article↗
PubMed2000

beta-cyanoalanine production by marine bacteria on cyanide-free medium and its specific inhibitory activity toward cyanobacteria.

In screening the culture broth of marine bacteria collected at Yap (Micronesia), Palau (Belau), and Okinawa (the southwest islands of Japan) for antimicroalgal activity, 37 out of 2,594 bacterial isolates tested were found to produce anticyanobacterial substances against Oscillatoria amphibia NIES-361. One strain, C-979, identified as a Vibrio sp., was selected and cultured in 2.4 liters of marine broth 2216 to identify the bioactive compound produced by the strain. The purified very hydrophilic compound (16.4 mg) was determined to be beta-cyano-L-alanine (L-CNAla) by instrumental analyses and the application of the advanced Marfey method. L-CNAla did not inhibit the growth of bacteria, yeast, or eukaryotic microalgae, but some cyanobacteria were found to be sensitive to L-CNAla at a concentration of 0.4 to 25 microg/ml. The effect of L-CNAla on some other environmental organisms, including invertebrates and a macroalgae, is discussed. CNAla production in marine broth was examined by thin-layer chromatography for the 37 bacterial isolates which produced an anticyanobacterial substance. The broth of 36 of these strains contained CNAla, suggesting the wide distribution of CNAla production by marine bacteria. This is the first report on bacteria that produce CNAla without a supply of the cyanide ion in the medium.

Alanine↗
PubMed2004

Biosynthetic gene cluster of the herbicide phosphinothricin tripeptide from Streptomyces viridochromogenes Tü494.

The antibiotic phosphinothricin tripeptide (PTT) consists of two molecules of L-alanine and one molecule of the unusual amino acid phosphinothricin (PT) which are nonribosomally combined. The bioactive compound PT has bactericidal, fungicidal, and herbicidal properties and possesses a C-P-C bond, which is very rare in natural compounds. Previously uncharacterized flanking and middle regions of the PTT biosynthetic gene cluster from Streptomyces viridochromogenes Tü494 were isolated and sequenced. The boundaries of the gene cluster were identified by gene inactivation studies. Sequence analysis and homology searches led to the completion of the gene cluster, which consists of 24 genes. Four of these were identified as undescribed genes coding for proteins that are probably involved in uncharacterized early steps of antibiotic biosynthesis or in providing precursors of PTT biosynthesis (phosphoenolpyruvate, acetyl-coenzyme A, or L-alanine). The involvement of the genes orfM and trs and of the regulatory gene prpA in PTT biosynthesis was analyzed by gene inactivation and overexpression, respectively. Insight into the regulation of PTT was gained by determining the transcriptional start sites of the pmi and prpA genes. A previously undescribed regulatory gene involved in morphological differentiation in streptomycetes was identified outside of the left boundary of the PTT biosynthetic gene cluster.

Amino Acid Sequence↗
PubMed2004

Development of a universal microarray based on the ligation detection reaction and 16S rrna gene polymorphism to target diversity of cyanobacteria.

The cyanobacteria are photosynthetic prokaryotes of significant ecological and biotechnological interest, since they strongly contribute to primary production and are a rich source of bioactive compounds. In eutrophic fresh and brackish waters, their mass occurrences (water blooms) are often toxic and constitute a high potential risk for human health. Therefore, rapid and reliable identification of cyanobacterial species in complex environmental samples is important. Here we describe the development and validation of a microarray for the identification of cyanobacteria in aquatic environments. Our approach is based on the use of a ligation detection reaction coupled to a universal array. Probes were designed for detecting 19 cyanobacterial groups including Anabaena/Aphanizomenon, Calothrix, Cylindrospermopsis, Cylindrospermum, Gloeothece, halotolerants, Leptolyngbya, Palau Lyngbya, Microcystis, Nodularia, Nostoc, Planktothrix, Antarctic Phormidium, Prochlorococcus, Spirulina, Synechococcus, Synechocystis, Trichodesmium, and Woronichinia. These groups were identified based on an alignment of over 300 cyanobacterial 16S rRNA sequences. For validation of the microarrays, 95 samples (24 axenic strains from culture collections, 27 isolated strains, and 44 cloned fragments recovered from environmental samples) were tested. The results demonstrated a high discriminative power and sensitivity to 1 fmol of the PCR-amplified 16S rRNA gene. Accurate identification of target strains was also achieved with unbalanced mixes of PCR amplicons from different cyanobacteria and an environmental sample. Our universal array method shows great potential for rapid and reliable identification of cyanobacteria. It can be easily adapted to future development and could thus be applied both in research and environmental monitoring.

Bacterial Typing Techniques↗