Capillary electrophoresis as a simple and sensitive method to study polysaccharides of Sinorhizobium sp. NGR234

We report the minimum amounts of polysaccharides (6.5 ng) that can be studied using capillary electrophoresis-laser-induced fluorescence (CE-LIF) and describe the separation of the various monosaccharides susceptible to occur in Sinorhizobium cell wall. On-gel hydrolysis of the polysaccharides is described. It allowed the easy and rapid determination of the monosaccharide composition of the excised lipopolysaccharides. The composition obtained fits with gas chromatography-mass spectrometry (GC-MS) results. This study underlines the simplicity of using CE-LIF, which remains an entirely "water medium" method, unlike GC-MS which is, in addition, less sensitive (at least 100-fold) than CE-LIF.     

Synthesis of vinca alkaloids and related compounds 99<Superscript>1</Superscript>. A new heterocyclic system

Utilising our earlier intermediate obtained by the umpolung reactivity of quinolizidine enamines, a new heterocyclic system: (11bSR, 15aSR)-1,2,3,6,11,14,15,15a-Octahydro-5H-indolo [2′,3′:3,4]pyrido[2,1-j]-1,6-naphthyridin-13(12H)-one was synthesised and its biological effects evaluated. Although modest, significant and selective effects were detected.     

Synthesis and structure of tricyclic furanosesquiterpenoids related to pallescensin A

Electrophilic cyclization of (cyclo)farnesanes containing anexo-methylene group in the a-isoprenoid unit smoothly gives regio- and stereoisomeric octalins subsequently transformed to tricyclic furanosesquiterpenoids related to metabolites of some marine organisms.Deceased.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 156–163, January, 1994.The authors are grateful to the representative of the Bruker company in Moscow, Uve Eichhof, who allowed us to use an AMX-400 spectrometer.     

Di-isophorone and related compounds. Part 8 1-aminodi-isophorane dericatives

The interaction of 1-chlorodi-isophor-2(7)-en-3-one or its 5.11-bisnor-homologue with potassium phthalimide yields the corresponding 1-phthalimido-compounds, which are converted into the 1-amines on treatment with hydrazine, followed by hydrolysis. 1-Aminodi-isophor-2(7)-ene is not accessible by this route, but its N-acyl-derivatives are obtainable directly from 1-hydroxydi-isophor-2(7)-ene by theRitter reaction; the 3-keto-analogue reacts similarly. Some properties of the novel 1-aminodi-isophoranes are described.Die Einwirkung von Phthalimid-Kalium auf 1-Chlor-di-isophor-2(7)-en-3-on oder sein 5,11-Bis-nor-Homolog ergibt die entsprrechenden 1-Phthalimido-Ver Verbindungen, aus welchen durch Behandlung mit Hydrazin und darauffolgende Hydrolyse die primären 1-Amine erhältlich sind. 1-Amino-di-isophor-2(7)-en ist auf diese Weise nicht darstellbar, aber seine N-Acyl-derivate sind direkt aus 1-Hydroxy-di-isophor-2(7)-en mittels derRitter-Reaktion zugänglich; die analoge 3-Keto-verbindung reagiert ebenso. Einige Eigenschaften der neuen 1-Amino-di-isophorane werden beschrieben.Part 7:Kurzer, F., Morgan, A. R., Mh. Chem.112, 129 (1981).     

Biosorption of lead(II) from aqueous solutions by non-living algal biomass Oedogonium sp. and Nostoc sp.--a comparative study

Industrial wastewaters containing heavy metals pose a major environmental problem that needs to be remedied. The present study reports the ability of two non-living (dried) fresh water algae, Oedogonium sp. and Nostoc sp. to remove lead(II) from aqueous solutions in batch system under varying range of pH (2.99-7.04), contact time (5-300 min), biosorbent dose (0.1-0.8 g/L), and initial metal ion concentrations (100 and 200mg/L). The optimum conditions for lead biosorption are almost same for the two algal biomass Oedogonium sp. and Nostoc sp. (pH 5.0, contact time 90 and 70 min, biosorbent dose 0.5 g/L and initial Pb(II) concentration 200mg/L) however, the biomass of Oedogonium sp. was found to be more suitable than Nostoc sp. for the development of an efficient biosorbent for the removal of lead(II) from aqueous solutions, as it showed higher values of q(e) adsorption capacity (145.0mg/g for Oedogonium sp. and 93.5mg/g for Nostoc sp.). The equilibrium data fitted well in the Langmuir isotherms than the Freundlich isotherm, thus proving monolayer adsorption of lead on both the algal biomass. Analysis of data shows that the process involves second-order kinetics and thermodynamic treatment of equilibrium data shows endothermic nature of the adsorption process. The spectrum of FTIR confirms that the amino and carboxyl groups on the surface of algal biomass were the main adsorption sites for lead removal. Both the biosorbents could be regenerated using 0.1 mol/L HCl solution, with upto 90% recovery. The biosorbents were reused in five biosorption-desorption cycles without a significant loss in biosorption capacity. Thus, this study demonstrated that both the algal biomass could be used as an efficient biosorbents for the treatment of lead(II) bearing wastewater streams.     

Overproduction of riboflavin by anArthrobacter sp. mutant resistant to 5-fluorouracil

Effects of pH and dissolved oxygen concentration on batchwise riboflavin production by a 5-fluorouracil (5-FU)-resistant mutant ofArthrobacter sp. were investigated. The reaction was carried out in a jar fermentor. The optimal pH of culture medium was around 7.3. Dissolved oxygen concentration was almost constant during fermentation at 600 rpm of agitation rate. Production of riboflavin reached a maximum of 160 mg/L after 70 h fermentation under the agitation rate of 600 rpm, aeration rate of 1.0 L/min, and pH 7.0.     

Di-isophorone and related compounds. Part 6. The action of nucleophiles on 8-bromodi-isophorone

Hydrolysis and acetolysis of 8-bromo-1-hydroxydi-isophor-2(7)-en-3-one yields both epimeric forms of the corresponding 4-hydroxy and 4-acetoxy-compounds, probably by a mechanism involving a bimolecular (SN2) displacement. The action of excess of hydrazine on the same reactant occurs with evolution of ammonia, to produce good yields of 4-hydrazono-1-hydroxydi-isophor-2(7)-en-3-one. This is convertible into N- and O-acyl derivatives, but its 3-oxo-group fails to raact with the usual ketonic reagents. Instead, its 4-hydrazono-group is displaced by substituted hydrazines and semicarbazides in an exchange process (transhydrazination).Part 5:A. A. Allen, F. Kurzer, andA. R. Morgan, J. C. S. Perkin I1980, 733.     

Ab initio program for treatment of related molecules. I. Integral part

Anab initio integral program is described. It utilizes the local symmetries to avoid the redundant computation of integrals over spatially equivalent subsets of the basis. The integrals are grouped in a particular way to facilitate their transfer. The program is very suitable for the treatment of related systems with model geometries. The computing times of different programs are compared and the efficiency of the presented one is demonstrated.     

Di-isophorone and related compounds. Part 7. Syntheses and properties of 1-hydroxydi-isophor-2(7)-ene-3,4-dione

1-Hydroxydi-isophor-2(7)-ene-3,4-dione (4), the -diketone derived from the parent di-isophorone, is obtained by several routes. Its formation by the hydrogenation of the corresponding 2,7-epoxide3 confirms its assigned structure. The action of alkali on 4-substituted 8-bromodi-isophor-2(7)-en-3-ones yields, presumably by a successive bimolecular (SN2) substitution and hydrolysis, the 4,4-dihydroxy-precursor, from which the 3,4-diketone4 arises by loss of water. In yet another approach,4 is produced by the hydrolysis of its 4-monohydrazone, which is independently accessible from 8-bromo-1-hydroxydi-isophor-2(7)-en-3-one (8). In acidic media, the yellow diketone4 enolises to the stable isolable colourless 1,3-dihydroxydi-isophora-2,7-dien-4-one (19); the action of alkali reverses the process. Both forms of the compound yield the same 1-acyl-derivatives and 4-hydrazones.Part 6:Davies, P. R., Kurzer, F., Morgan, A. R. Mh. Chem.111, 1097 (1980).     

Purines, pyrimidines, and related fused systems. 20. Heterocyclizations of 6-alkynyl-1,3-dimethyllumazines. Synthesis of pyrrole and thiophene analogs of some natural pteridines

Sonogashira cross-coupling of 6-chloro-1,3-dimethyllumazine with terminal alkynes gave 6-alkynyl derivatives in good yields. Oxidative amination of the latter with primary alkylamines was accompanied by the pyrrole-ring closure to form 1-R"-2-R-6,8-dimethylpyrrolo[3,2-g]pteridine-5,7(6H,8H)-diones. The addition of bromine to 6-alkynyllumazines afforded the corresponding dibromoalkenes whose treatment with sodium trithiocarbonate gave rise to 2-R-6,8-dimethylthieno[3,2-g]pteridine-5,7(6H,8H)-diones. The latter compounds are close analogs of the metabolite of molybdenum cofactor (molybdopterine).     

Synthesis of 20S-protopanaxadiol 20-O-β-D-glucopyranoside, a metabolite of Panax ginseng glycosides, and compounds related to it

A preparative semi-synthetic method was developed to prepare 20S-protopanaxadiol 20-O-β-Dglucopyranoside (1), a metabolite of Panax ginseng glycosides. The 20-O-•-D-glucopyranosides of 20S-hydroxydammar-24-en-3,12-dione, 3β,20S-dihydroxydammar-24-en-12-one, and 3β,12α, 20S-trihydroxydammar-24-ene were synthesized for the first time. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 364–369, July–August, 2006.     

Characterization of a kerationlytic metalloprotease from Bacillus sp. SCB-3

A keratinolytic protease-producing microorganism was isolated from soybean paste waste and was identified as a strain of Bacillus sp. The keratinase was purified by polyethylene glycol precipitation and two successive column chromatographies with DEAE-Toyopearl 650C and Sephacryl S-200 HR. The purified enzyme had overall 11 purification folds with an 18% yield. The results of sodium dodecyl sulfate polyacrylamide gel electrophoresis and gel filtration on Sephacryl G-200 indicated that the purified enzyme was monomeric and had a molecular weight of 134 kDa. The optimum temperature and pH were 40°C and 7.0, respectively. This enzyme was completely inhibited by EDTA and EGTA, and it was restored by the addition of Ca⁺² and Mg⁺². These results suggested that it is a metalloprotease. The stimulated enzyme activity by reducing agents indicated that the reducing condition was important in the expression of the activity.     

Isolation and characterization of thermophilic benzothiophene-degrading Mycobacterium sp.

A bacterial strain, SWU-4, capable of using benzothiophene (BT) as a sole carbon and energy source was isolated from a petroleum-contaminated site in Thailand and identified by 16S rRNA gene sequence analysis to be in the genus of Mycobacterium. The strain was Gram-positive, nonspore former, and grew at 50° C. Colonies of the strain on nutrient agar were rod-shaped, smooth with a convex surface, slightly mucoid, and yellow pigmented. The thermophilic Mycobacterium sp. strain SWU-4 rapidly degraded 2% (w/v) BT at 50°C. Interestingly, this strain was able to degrade a wide variety of organosulfur compounds including thiophene, bromo(α)thiophene, and 3-methylthiophene in liquid minimum medium at 50°C, which will be beneficial for industrial applications.     

Ubiquinone Q9 from a marine isolate of an actinobacterium Nocardia sp.

The major component of a nonpolar fraction of an extract of an actinobacterium Nocardia sp. KMM 3749 isolated from an unidentified marine ascidian was shown, using NMR spectroscopy and mass spectrometry, to be 2,3-dimethoxy-5-methyl-6-polyprenyl-1,4-benzoquinone (ubiquinone Q₉).     

Porphyrins. 37. Synthesis of heterodimers of porphyrins and chlorins containing pyrrolyl-methyl bridges

We have obtained various adducts, including homodimers and heterodimers of ethanebisporphyrins and ethanebischlorins containing pyrrole and dipyrrylmethane insertions, by reaction of mesodimethylaminomethylporphyrins and chlorins with -unsubstituted pyrrole derivatives in the presence of methyl iodide.For Communication 36, see [1].Dedicated to Professor M. A. Yurovskaya on her Jubilee.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 336–341, March, 2000.     

Characteriztion of a novel feather-degrading Bacillus sp. strain

Feather waste is generated in large amounts as a byproduct of commercial poultry processing. This residue is almost pure keratin, which is not easily degradable by common proteolytic enzymes. A feather-degrading bacterium was isolated from poultry feathers in decomposition. The strain identified as kr16 showed important feather-degrading activity when grown on basal medium containing 10 g/L of native feather as the source of energy, carbon, and nitrogen. The isolate was characterized according to the phenotypical characteristics and biochemical profiling that belong to the Bacillus genus. Keratinolytic activity of this isolate was monitored during cultivation of the bacterium on raw feathers at different temperatures. Maximum growth and feather-degrading activity were observed at 30–37°C. The keratinolytic enzyme had a pH optimum ranging from 8.0 to 11.0 and a temperature optimum of 45–65°C. The keratinase was strongly inhibited by EDTA and the metal ions Hg²⁺ and Sn²⁺.     

Synthesis of dipyridyl sulfides from pyridyl-pyridinium halides

Reactions of pyridyl-pyridinium halides with thiolpyridines and thiourea were investigated. New dipyridyl sulfides were obtained by this method.

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Synthese von Dipyridil-sulfiden aus Pyridil-pyridinium-halogeniden

Zusammenfassung Reaktionen von Pyridil-pyridinium-halogeniden mit Thiolpyridinen und Thioharnstoff werden untersucht. Auf diesem Weg wurde eine Reihe neuer Dipyridil-sulfide synthesiert.

     

Exopolysaccharide production by a marine cyanobacterium Cyanothece sp.

The adsorption and the hydrolytic action of purified cellulases of Trichoderma reesei, namely, cellobiohydrolase I (CBH I), endoglucanase II (EG II), and their core proteins, on steam-pretreated willow were compared. The two enzymes differed clearly in their adsorption and hydrolytic behavior. CBH I required the cellulose-binding domain (CBD) for efficient adsorption and hydrolysis, whereas EG II was able to adsorb to steam pretreated willow without its CBD. Absence of the CBD decreased the hydrolysis of cellulose by EG II, but the decrease was less pronounced than with CBH I. A linear relationship was observed between the amount of enzyme adsorbed and the degree of hydrolysis of cellulose only for CBHI. EG II and EG II core appeared to be able to hydrolyze only 1 to 2% of the substrate regardless of the amount of protein adsorbed.     

Geminal systems. 50. Synthesis and alcoholysis of N-acyloxy-N-alkoxy derivatives of ureas,carbamates, and benzamides

Procedures were developed for the synthesis of N-acyloxy-N-alkoxy derivatives of ureas, carbamates, and benzamides by the reactions of the corresponding N-alkoxy-N-chloro derivatives with sodium carboxylates in MeCN. N-Chloro-N-ethoxy-p-toluenesulfonamide was inert in this reaction. Alcoholysis of N-acyloxy-N-alkoxy derivatives of ureas, carbamates, and tert-alkylamines afforded the corresponding N,N-dialkoxy derivatives, whereas alcoholysis of N-acetoxy-N-ethoxybenzamide gave rise to alkyl benzoates.