Poly Sulfate Research Articles

Characterization of Exo 1, 4-<i>β</i> glucanase produced from <i>Tricoderma Viridi</i> MBL through solid-state bio-processing of orange peel waste

Agro-industrial residues are primarily composed of complex polysaccharides that strengthen the microbial growth for the production of industrially important enzymes like cellulases. In the present study we aimed to characterize the Exo 1, 4-β glucanase that was indigenously produced from Trichoderma viride MBL. T. viride MBL was cultured in the Solid-State medium of orange peel (50% w/w moisture) under optimized fermentation conditions and maximum activity of 412 ± 12 U/mL was recorded after 4th day of incubation at pH 5.5 and 30℃. Exo 1, 4-β glucanase was 4.17-fold purified with specific activity of 642 U/mg in comparison to the crude extract. To confirm its purity and molecular weight, sodium dodecyl sulphate poly acrylamide gel electrophoresis (SDS- PAGE) was performed. The enzyme was shown to have a molecular weight of 60 kDa with an optimum pH and temperature of 5 and 50℃, respectively. Lineweaver-Burk reciprocal plot revealed that the kinetic constants Km and Vmax of purified Exo 1, 4-β glucanase were 76 μM and 240 U/mL.

The effect of extracted bacterial LPS from Salmonella enteritidis on COX-2 in hepg2 cell line in induction and inhibition conditions

Hepatocellular carcinoma is the fifth most common neoplasm and the most important cause of death in patients with liver cirrhosis in the world. lipopolysaccharide (LPS) stimulates the hepatocyte cells and increases the production of inducible cytokine with the high production of nitric oxide and ROS. Chronic inflammation caused by lipopolysaccharide directly activates immune system and indirectly, through COX-2 interferes in the formation of malignant disease. In this study, the rate change of COX-2 was searched by adding LPS and also the effect of inhibition of this inflammatory enzyme by Celecoxib and combined effect of this in HepG2 cancer cells was assessed. Salmonellaenteritidis lipopolysaccharide is extracted by methanol-chloroform method and the Sodium dodesyl sulfate poly acryl-amide gel electrophoresis (SDS-PAGE) electrophoresis bands were stained by silver nitrate. Four treatment groups of HepG2 cells were stimulated with 100 ng/ml LPS, 500 µM Celecoxib as inhibitor and were incubated for 12 and 24 h. Variables including both increase and decrease inflammatory factor, COX-2, was assayed. The obtained results showed that initial activity of COX-2 in not stimulated in HepG2 cell, 1.957 ng/ml after stimulation with LPS for 12 and 24 h (1.383 and 0.618 ng/ml) decreased and the effect of this inhibitor was also studied. The data showed that the reduction of COX-2 in HepG2 cells was correlated with the cell density and duration of incubation with LPS. Inhibition of enzyme associated with inflammation, with inhibitor substance; celecoxib, observed as well as LPS. We can potentially design drugs to treat a variety of diseases and cancers. Key words: Cyclooxygenase-2, HepG2 Cell, Salmonella enteritidis,lipopolysaccharide, Sodium dodesyl sulfate poly acryl-amide gel electrophoresis (SDS-PAGE).

Characterization of leucine amino peptidase from Streptomyces gedanensis and its applications for protein hydrolysis

The aim of this work was to purify and characterize the extra-cellular leucine amino peptidase (LAP) from Streptomyces gedanensis and also study its applications for protein hydrolysis. The enzyme was purified to homogeneity by ammonium sulfate fractionation and sequential chromatography steps. LAP appeared to be a monomeric enzyme with a molecular weight of ∼75 kDa determined by sodium dodecyl sulfate poly acryl amide gel electrophoresis (SDS-PAGE). The enzyme preferentially hydrolyzed leucine p-nitroanilide followed by Met, Phe, Lys and Arg derivatives. Kinetic studies on the purified enzyme confirmed that it can hydrolyze peptide as well as ester substrates at comparable rates. This amino peptidase was highly resistant to different concentrations of various organic solvents. The characteristics of this amino peptidase, including thermo stability, organic solvent resistance, its activity against various substrates, and also it showed esterase and peptidase activity at comparable rates; identified this amino peptidase as a novel one. The specificity towards aromatic and hydrophobic amino acid residues, the solvent-resistance and thermo stability make this amino peptidase could offer interesting possibilities for various industrial applications including debittering of protein hydrolysates, peptide and ester synthesis.

Characterization of a novel manganese peroxidase purified from solid state culture of Trametes versicolor IBL-04

A novel manganese peroxidase (MnP) produced by an indigenous white rot fungal strain Trametes versicolor IBL-04 in solid state medium of corncobs was purified and characterized. The fungus produced 964U/mL MnP in the presence of additional carbon (glucose) and nitrogen (yeast extract) supplements added at a C:N ratio of 25:1, 1mM Tween-80 (1mL), 1mM MnSO4 (1mL), and 1mM CuSO4 (1mL). The MnP was purified by ammonium sulfate fractionation (65% saturation) and dialysis, followed by Sephadex G-100 gel filtration chromatography. Purification procedures resulted in 2.4-fold purification with an overall yield and specific activity of 3.4% and 660 U/mg, respectively. The purified MnP was monomeric of molecular weight of 43 kDa, showing a single band on sodium dodecyl sulfate poly acrylamide gel electrophoresis (SDS-PAGE). The enzyme was optimally active at pH 5 and 50oC and was stable for 1 h over a broad range of pH (4-7) and temperature (40-65oC). Kinetic constants KM and Vmax of purified MnP were 70 µM and 540 U/mL for MnSO4 substrate. The effect of possible activators and inhibitors of enzyme were also investigated, and it was observed that EDTA, Cystein, and Ag+ caused MnP inhibition and inactivation to different extents, whereas MnP was activated by 4 and 3 mM of Cu2+ and Fe2+, respectively. High thermo-stability, low KM and high Vmax features of this novel MnP isolated from culture filtrate of T. versicolor IBL-04 suggests its suitability for various industrial and biotechnological applications.

Serum Immunoglobulin M (IgM) in Sakhalin Taimen (Hucho perryi): Purification, Characterization, Circulating Levels, and Specific IgM Production by the Parasitic Salmincola stellatus

Immunoglobulin M (IgM) was purified from the serum of Sakhalin taimen (Hucho perryi) by salting-out, ion-exchange chromatography on DEAE-cellulose, and gel filtration on Sepharose 6B. The intact, tetrameric taimen IgM has a mass of 750 kDa with molecular architec- ture typical of IgM from other salmonids. The molecular weights of heavy (μ) chain and light chains (L) of the IgM monomer were estimated to be 68 kDa and 23 kDa, respectively. Purified taimen IgM was used to raise a specific rabbit antiserum and to develop a single radial immunodif- fusion assay for measuring circulating IgM levels. The serum IgM levels in captive, immature or maturing female taimen varied between 1 and 5 mg/ml, showing seasonal changes regardless of fish age, with relatively low levels in spring and conversely high levels in autumn. Production of specific serum IgM to a parasite, Salmincola stellatus, was assessed by sodium dodecyl sulfate poly- acrylamide gel electrophoresis (SDS-PAGE) and immunoblotting. The parasitized taimen serum could react with protein components of aqueous extracts from the parasite that were blotted on a nitrocellulose membrane after SDS-PAGE, but normal taimen serum did not, indicating that the parasitized fish produced the specific IgM to S. stellatus in the serum.

Smart PEGylation of Trypsin

Thermoresponsive oligo(ethylene glycol)-based copolymers were investigated for trypsin conjugation. These copolymers have been synthesized by atom transfer radical polymerization of 2-(2-methoxyethoxy)ethyl methacrylate (MEO(2)MA) with oligo(ethylene glycol) methyl ether methacrylate (OEGMA(475), M(n) = 475 g.mol(-1)) at 60 degrees C in the presence of copper(I) chloride and 2,2'-bipyridyl. Two different ATRP initiators, containing succinimidyl ester moieties, were tested, namely, N-succinimidyl-2-bromopropionate and N-succinimidyl-2-bromoisobutyrate. In both cases, ATRP afforded well-defined polymers with a narrow molecular weight distribution and controlled chain-ends. However, the efficiency of initiation of the two initiators was lower than 1 and therefore the formed polymers exhibited a higher than expected mean degree of polymerization. Nevertheless, all types of polymers could be conjugated to trypsin. The conjugation reaction was performed in borax-HCl buffer. Sodium dodecyl sulfate poly(acrylamide) gel electrophoresis (SDS-PAGE) indicated that polymer/enzyme conjugates were obtained in all cases. However, (co)polymers initiated by N-succinimidyl-2-bromopropionate led to the best conjugation results. The formed P(MEO(2)MA-co-OEGMA(475))-trypsin conjugates were found to be thermoresponsive and moreover exhibited a higher enzymatic activity than unmodified trypsin.

Molecular Cloning and Expression of Bacterial Mercuric Reductase Gene

In order to characterize the bacterial mercuric reductase (merA) gene, mercury resistant (Hgr) Escherichia coli strains have been isolated from various mercury contaminated sites of India. Their minimum inhibitory concentration (MIC) for Hg and zone of inhibition for different antibiotics were measured, and finally mer operon was localized by transforming isolated E. coli plasmid into mercury sensitive (Hgs) host E. coli DH5a cells. Oligonucleotide primers were designed by comparing the known reported sequences of merA from Gram-negative bacterium (E. coli plasmid R100) and 1695 bp full length merA gene was amplified by PCR. A 1.695-kb DNA fragment of merA was inserted into isopropyl-
-D-thiogalactopyranoside (IPTG) inducible bacterial expression vector pQE-30U/A. E. coli DH5 strains harboring the merA constructs showed higher mercury reductase enzyme (MerA) activity and expressed significantly more MerA than the control strains under aerobic conditions. The purified merA gene over expressed in the specific host E. coli BL21(DE3)Plys cells. Finally, expressed MerA protein was purified by Immobilized Metal-chelate Affinity Chromatography (IMAC) by using Ni- NTA column; and ~66.2 kDa bacterial MerA protein was detected after resolving on 10% sodium dodecyl sulphate poly acrylamide gel electrophoresis (SDS PAGE).

Production and partial purification of invertase using Cympopogan caecius leaf powder as substrate

The present study investigates the efficiency of Aspergillus niger to produce invertase, an industrially important enzyme by using powdered stem of Cympopogan caecius (Lemon grass) as sole substrate and sole carbon source for the microorganism. The molecular weight of invertase was estimated to be 66-70 kDa by sodium do decyl sulphate poly acrylamide gel electrophoresis (SDS PAGE). The production of the enzyme was studied at different pH scales ranging from pH 4.0 to 7.0 at a constant temperature of 30°C and 2% substrate concentration. The maximum production of invertase (specific activity -0.0516 μk/mg protein) was obtained at pH 5.5 at 30°C temperature, and incubation for 48 h. The activity was found to be stable at pH 5.5 for 30 min. The enzyme was found to be stable in the temperature range of 20-55°C. The effect of divalent metal ions Cu(2+), Fe(2+), Co(2+) on the activity of the enzyme invertase showed that these ions affected the activity by a certain factor. The study can be further industrially exploited in a country-like India where lemon grass is found in plenty and can be used as substrate for enzyme production. Moreover, the preparation of the substrate is also a simple process.

Fluorescence spectroscopy of small peptides interacting with microheterogeneous micelles

Many peptides containing tryptophan have therapeutic uses and can be studied by their fluorescent properties. The biological activity of these peptides involves interactions with many cellular components and micelles can function as carriers inside organisms. We report results from the interaction of small peptides containing tryptophan with several microheterogeneous systems: sodium dodecyl sulphate (SDS) micelles; sodium dodecyl sulphate–poly(ethylene oxide) (SDS–PEO) aggregates; and neutral polymeric micelles. We observed that specific parameters, such as wavelength of maximum emission and fluorescence anisotropy, could be used to ascertain the occurrence of interactions. Affinity constants were determined from changes in the intensity of emission while structural modifications in rotameric conformations were verified from time-resolved measurements. Information about the location and diffusion of peptides in the microheterogeneous systems were obtained from tryptophan emission quenching experiments using N-alkylpyridinium ions. The results show the importance of electrostatic and hydrophobic effects, and of the ionization state of charged residues, in the presence of anionic and amphiphilic SDS in the microheterogeneous systems. Conformational stability of peptides is best preserved in the interaction with the neutral polymeric micelles.

Experimental Design and Multivariate Analysis for Optimizing Poly(d,l-lactide-co-glycolide) (PLGA) Nanoparticle Synthesis Using Molecular Micelles

The utility of polymeric nanoparticles as drug delivery systems depends on effective control of synthetic parameters with a significant impact on their physico-chemical characteristics. In this study, a chemometric central composite experimental design (CCD) was used to optimize the synthesis of poly(D,L-lactide-co-glycolide) (PLGA) nanoparticles by emulsification solvent evaporation using anionic molecular micelles, such as poly(sodium N-undecylenic sulfate) (poly-SUS), poly(sodium N-undecanoyl-glycinate) (poly-SUG) and poly(sodium N-undecanoyl-L-leucyl-valinate) (poly-L-SULV) as well as conventional emulsifiers, such as anionic sodium dodecyl sulfate (SDS) and non-ionic poly(vinyl alcohol) (PVA). The individual and combined effects of PLGA concentration, emulsifier concentration, homogenization speed, and sonication time (design variables) on particle size and polydispersity index (responses) were investigated using multivariate analysis. The most significant design variables influencing the nanoparticle size and size distribution were PLGA concentration and emulsifier concentration (p < 0.05) in comparison to the other design variables. The quadratic model demonstrated the highest predictive ability when the molecular micelles were used as emulsifiers. The PLGA nanoparticles optimally synthesized according to the CCD were further purified by dialysis and then freeze-dried. Dried nanoparticles synthesized with molecular micelles and PVA were readily re-suspended in water, as compared with SDS for which nanoparticle aggregation occurred. The size of PLGA nanoparticles synthesized using molecular micelles increased after freeze-drying, but remained smaller than 100 nm when poly-L-SULV was used as emulsifier. The PDI values indicated monodisperse nanoparticle suspensions after purification and freeze-drying for all investigated molecular micelles (PDI < 0.100). The nanoparticle suspensions synthesized using molecular micelles were the most stable after dialysis and freeze-drying, having low negative zeta potential values ranging from -54 +/- 1.6 mV for poly-L-SULV to -63.2 +/- 0.4 mV for poly-SUS. Transmission electron microscopy (TEM) micrographs showed spherical shape and smooth surface for the PLGA nanoparticles synthesized using molecular micelles.

Improvement of the stability of glucose oxidase via encapsulation in sodium alginate–cellulose sulfate–poly(methylene- co-guanidine) capsules

Encapsulation of glucose oxidase (GOD) in polyelectrolyte complex capsules and its influence on properties of the enzyme is reported. The immobilization of GOD in the capsules made of sodium alginate (SA), cellulose sulfate (CS), poly(methylene- co-guanidine) (PMCG), CaCl 2 and NaCl (GOD–SA–CS/PMCG capsules) was achieved using a one-step highly reproducible encapsulation protocol which was monitored by a Electrospray Ionization-Mass Spectrometry (ESI-MS). A leakage of the enzyme from the capsules was negligible. Encapsulated GOD exhibited higher thermostability, wider range of pH optimum and improved storage stability in comparison with free GOD. The 92% retained activity by the encapsulated GOD after 45 biooxidation cycles was markedly higher than that of the GOD entrapped in calcium pectate gel beads showing no activity after 12 cycles. Optimization of conditions of oxygen supplementation resulted in increased oxygen availability within the GOD–SA–CS/PMCG capsules. Oxygen supplementation was accompanied with a mild decrease in the mechanical resistance of the SA–CS/PMCG capsules.

Affinity-capture protease reactor for single-step production and purification of antiangiogenic plasminogen fragment from human plasma

Bait and Snip Affinity columns have been around for many years, as have immobilized protease reactor columns. The latter are used to cleave precursor molecules into an active form by passing over a column containing immobilized enzymes. Now, Shimizu and Hasumi (p. 590) have combined these two concepts to create a facile means to proteolytically remove and isolate an active cleavage product from its precursor. The advantage of this affinity capture reactor system is that it allows initial concentration on the column of the substrate from a crude mixture, followed by cleavage under conditions that are more favorable for maintaining substrate activity and preventing denaturation. Final purification of the cleaved product is also simplified. To demonstrate the application of the system, the authors covalently immobilized lysine, which binds to plasminogen, plus the metalloproteinase bacillolysin MA (BL-MA) on a sepharose column, over which was passed crude human plasma. Plasminogen in the plasma bound to the ...

Nocardia tartaricans cells immobilized in sodium alginate–cellulose sulfate–poly (methylene‐co‐guanidine)capsules: mechanical resistance and operational stability

AbstractThe stereospecific hydrolysis of cis‐epoxysuccinate (CES) to L‐(+)‐tartrate, catalysed by the action of CES hydrolase activity in whole Nocardia tartaricans bacterial cells, has been chosen as a model biotransformation system. The performance of cells was studied by immobilization in polyelectrolyte complex (sodium alginate–cellulose sulfate–poly(methylene‐co‐guanidine, SA–CS/PMCG) capsules based on sodium alginate and cellulose sulfate as polyanions, poly(methylene‐co‐guanidine) as polycation, CaCl2 as gelling agent and NaCl as antigelling agent. The encapsulated cells showed a preservation of 80% of the initial catalytic activity in encapsulated cells compared with 15% of retained catalytic activity in free cells after 10 repeated biotransformation cycles. Uniformity of batches of capsules was achieved by the use of an air‐stripping extrusion device fitted with a multiloop reactor. The capsules produced using this device had narrow standard deviations for capsule diameter (&lt;3%) and membrane thickness (&lt;6%). Monodisperse capsules are essential to ensure constant properties, including mechanical resistance and diffusional characteristics. Storage of capsules under different conditions revealed an approximate three‐fold decrease in bursting force after long‐term exposure to the highly sequestering CES, compared with capsules stored in 0.9% (w/v) NaCl. The molecular weight cut‐off of the capsular membrane, determined by inverse size exclusion chromatography, is in the range of the size of CES hydrolase. Copyright © 2006 Society of Chemical Industry

Micellar copolymerization of associative polymers: Study of the effect of acrylamide on sodium dodecyl sulfate–poly(propylene oxide) methacrylate mixed micelles

Mixed micelles of sodium dodecyl sulfate (SDS) and poly(propylene oxide) methacrylate (PPOMA) have been studied in the presence of acrylamide using conductimetry, fluorescence spectroscopy, and small-angle neutron scattering (SANS) under the following conditions: (i) the SDS–acrylamide binary system in water; (ii) the SDS–acrylamide–PPOMA ternary system in water. The addition of acrylamide in SDS solutions perturbs the micellization of the surfactant by decreasing the aggregation number of the micelles and increasing their ionization degree. The variations of the various micellar parameters versus the weight ratio R=PPOMA/SDS are different in the presence of acrylamide or in pure water. These differences are much more pronounced for the lower than for the higher PPOMA concentrations. There is competition between acrylamide and PPOMA and at higher PPOMA concentration, acrylamide tends to be released from SDS micelles and is completely replaced by PPOMA.

Direct Force Measurements between α-Alumina Surfaces with Adsorption of Anionic Surfactant/Polymer Mixtures

Direct measurements of interaction forces between α-alumina surfaces with coadsorbed anionic surfactant sodium dodecyl sulfate (SDS) and anionic polyelectrolyte poly(sodium 4-styrenesulfonate) (PSS) at pH 3.5 are carried out by colloidal probe atomic force microscopy. It is found that in aqueous PSS solutions the interaction forces are dependent on the initial PSS concentration. At low PSS concentration the electrostatic repulsion initially present is neutralized, resulting in a weak attraction between the surfaces, while as the concentration is increased further, repulsive forces reappear due to the additional adsorption of PSS on the surface. The adsorbed PSS adopts a relatively flat conformation at all PSS concentrations investigated. On the other hand, the interaction forces are dramatically different for the simultaneous addition of SDS and PSS: the force profile for the coaddition comes progressively close to that for the addition of SDS alone with increasing SDS concentration. This is attributed to the fact that SDS plays a key role for the coadsorption of SDS and PSS over a high SDS concentration region. The dispersion stability and ζ potential of α-alumina suspensions are evaluated for comparison with the resultant forces, and a good correlation is obtained between them. The effects of sequential addition of SDS and PSS are also investigated.

Differential Roles of TwoN-Acetylgalactosaminyltransferases, CSGalNAcT-1, and a Novel Enzyme, CSGalNAcT-2: INITIATION AND ELONGATION IN SYNTHESIS OF CHONDROITIN SULFATE

By a tblastn search with beta 1,4-galactosyltransferases as query sequences, we found an expressed sequence tag that showed similarity in beta 1,4-glycosyltransferase motifs. The full-length complementary DNA was obtained by a method of 5'-rapid amplification of complementary DNA ends. The predicted open reading frame encodes a typical type II membrane protein comprising 543 amino acids, the sequence of which was highly homologous to chondroitin sulfate N-acetylgalactosaminyltransferase (CSGalNAcT-1), and we designated this novel enzyme CSGalNAcT-2. CSGalNAcT-2 showed much stronger N-acetylgalactosaminyltransferase activity toward glucuronic acid of chondroitin poly- and oligosaccharides, and chondroitin sulfate poly- and oligosaccharides with a beta 1-4 linkage, i.e. elongation activity for chondroitin and chondroitin sulfate, but showed much weaker activity toward a tetrasaccharide of the glycosaminoglycan linkage structure (GlcA-Gal-Gal-Xyl-O-methoxyphenyl), i.e. initiation activity, than CSGalNAcT-1. Transfection of the CSGalNAcT-1 gene into Chinese hamster ovary cells yielded a change of glycosaminoglycan composition, i.e. the replacement of heparan sulfate on a syndecan-4/fibroblast growth factor-1 chimera protein by chondroitin sulfate, however, transfection of the CSGalNAcT-2 gene did not. The above results indicated that CSGalNAcT-1 is involved in the initiation of chondroitin sulfate synthesis, whereas CSGalNAcT-2 participates mainly in the elongation, not initiation. Quantitative real-time PCR analysis revealed that CSGalNAcT-2 transcripts were highly expressed in the small intestine, leukocytes, and spleen, however, both CSGalNAcTs were ubiquitously expressed in various tissues.

Differentiation of Pseudomonas Strains through PAGE Banding Pattern

Eleven Pseudomonas isolates of ten-plant species collected from all over Tamil Nadu were compared for their total cell proteins separated through sodium dodecyl sulphate poly acrylamide gel electrophoresis. AH the isolates showed marked variations among themselves and between fluorescent and non-fluorescent groups. However, similarity was observed with respect to three protein bands with molecular weight of 46, 43 and 32kDa. Data were scored based on the presence or absence of protein bands and cluster analysis was performed. The isolates from same location viz ., Coimbatore (PF1, PB2, COP1 and COT1), Sankaran Kovil (PSK1 and PSK2) and host (rice) showed greater level of similarity and occupied same cluster groups.

Novel Sulfated Oligosaccharides Containing 3-O-Sulfated Glucuronic Acid from King Crab Cartilage Chondroitin Sulfate K: UNEXPECTED DEGRADATION BY CHONDROITINASE ABC

We prepared a series of oligosaccharides from king crab cartilage chondroitin sulfate K after exhaustive digestion with testicular hyaluronidase, and determined the structures of four tetrasaccharides and a pentasaccharide by fast atom bombardment mass spectrometry, high performance liquid chromatography analysis of chondroitinase AC-II digests, and 500-MHz 1H NMR spectroscopy. The tetrasaccharides shared the common core structure GlcAbeta1-3GalNAcbeta1-4GlcAbeta1-3GalNAc with various sulfation profiles. One structure was GlcAbeta1-3GalNAc(4S)beta1-4GlcAbeta1-3GalNAc(4S), whereas three of them have the following hitherto unreported structures including a novel glucuronate 3-O-sulfate: GlcA(3S)beta1-3GalNAc(4S)beta1-4GlcAbeta1-3GalNAc(4S), GlcAbeta1-3GalNAc(4S)beta1-4GlcA(3S)beta1-3GalNAc(4S), and GlcA(3S)beta1-3GalNAc(4S)beta1-4GlcA(3S)beta1-3GalNAc(4S), where 3S or 4S represents 3-O- or 4-O-sulfate, respectively. The structure of the pentasaccharide was determined as GlcA(3S)beta1-3GalNAc(4S)beta1-4GlcA(3S)beta1- 3GalNAc(4S)beta1-4GlcA. Chondroitinase ABC digestion of the tetrasaccharides with GlcA(3S) at the internal position destroyed the disaccharide unit containing GlcA(3S) derived from the reducing side and resulted in only the disaccharide unit from the non-reducing side. In contrast, these tetrasaccharides remained totally resistant to chondroitinase AC-II. The results indicated that it is necessary to reevaluate the disaccharide composition of chondroitin sulfate poly- or oligosaccharides purified from various biological sources, since they were usually determined after chondroitinase ABC digestion. It is probable that the structures containing GlcA(3S) would not have been detected.

Identification of a Misleading Trypanosomatid Parasite from Gerbillus pyramidum and G. andersoni in a Leishmania major Endemic Area in North Sinai

During an epidemiologic investigation of cutaneous leishmaniasis at a focus in north Sinai, Egypt, between June 1989 and December 1991, 897 desert rodents were trapped and examined to identify reservoir hosts for Leishmania major. Mixed forms of epimastigotes and promastigotes were isolated in Tanabe's medium from 4 Gerbillus pyramidum and 1 Gerbillus andersoni. The 2 forms were later grown and separated as distinct cultures in Schneider's medium. The isoenzyme profile of the gerbils' promastigotes was identical to Leishmania tropica but differed from those of L. major and the gerbils' epimastigotes. The protein pattern by sodium dodecyl sulfate poly acrylamide gel electrophoresis gave no conclusive results. The Hae III restriction endonuclease analysis of kinetoplast DNA of both morphological forms confirmed their similarity and distinguished them from L. tropica and L. major. The gerbils' promastigotes were 30% broader, with a smaller nucleus than those of L. tropica. Following several subcultures, epimastigotes were found to transform to promastigotes. These observations suggest that the 2 forms belong to the genus Trypanosoma. Further studies are in progress to classify this putative Trypanosoma species whose promastigote stages display isoenzyme patterns identical to L. tropica, and which can be misidentified microscopically as Leishmania promastigotes.

オキシエチレン基の導入によるイオン性及び両性界面活性剤のタンパク質変性の低減効果

In order to widely investigate the reducing effects of protein denaturing potency of ionic and amphoteric surfactants by introducing oxyethylene residue in their structures, we synthesized 15 surfactants of five families, so called, [F-1] Dodecyl sulfate and dodecyl poly (ave. 2 and 4) oxyethylene sulfates, [F-2] N-dodecyl betain and N-dodecyl poly (ave. 2 and 4) oxyethylene betains, [F-3] N-tetradecyl betain and N-tetradecyl poly (avc. 2 and 4) oxyethylene betains [F-4] N-dodecyl-N, N-dimethyl amine oxide and N-dodecyl poly (ave. 2 and 4) oxyethylene-N, N-dimethyl amine oxides, and [F-5] N-dodecyl-N, N, N-trimethyl ammonium chloride and N-dodecyl poly (ave. 2 and 4) oxyethylene-N, N, N-trimethyl ammonium chlorides.The albumin protein denaturing potencies of these surfactants were measured on various concentrations.In above five families, especially in the case of [F-2], [F-3] and [F-4] we found that introducing oxyethylene residue in their structures gave remarkable reducing effects of albumine denaturing potencies.