Peptides-XXXXV: Synthesis of the 118–129 fragment of a lysozyme analogue

The synthesis of the (118–129) fragment of a Lysozyme analogue was achieved by the fragment coupling approach. The fragments were assembled using the DCCI/HONSu method and the (118–122), (123–126) and (127–129) subfragments were each built up in a stepwise manner. At several stages the diphenylphosphinic mixed anhydride method was found to be superior to the pivalic mixed anhydride method.     

Peptides—XXXXII: Synthesis of the 76–93 fragment of a lysozyme analogue

The synthesis of the (76–93) fragment of a lysozyme analogue was achieved using a fragment condensation approach employing the protected subfragments (76–79), (80–86), and (87–93). The utility of Bates' reagent in conjunction with N-hydroxysuccinimidc was examined for the linking of fragments. The resulting protected peptide (76–93) was found to be one of the most insoluble encountered in this whole programme directed towards the synthesis of a lysozyme analogue.     

Peptides-XXXIV: Synthesis of the 1–16 fragment of a lysozyme analogue

The synthesis of the 1–16 fragment of a lysozyme analogue is described. Three protected subfragments 1-4, 5-10 and 11-16 were combined using the N, N'-dicyclohexylcarbodiimide/N-hydroxysuccinimide method. The fully protected hexadecapeptide was purified by gel filtration on Sephadex LH-60 eluting with N-methylpyrrolidone.     

Chemical Studies of Formosan Cobra (Naja Naja Atra) Venom Part IV. Estimation of molecular weights of some purified protein fractions by sephadex gel filtration

Molecular weights of four purified fractions, Fractions VIII (cobraneurotoxin), IX (5′-nucleotidase), XI (cardiotoxin) and XII (cardiotoxin) of Formosan cobra venom were estimated by gel filtration on Sephadex G-100 and G-75 columns.     

Peptides—XXXXIV: Synthesis of the 105–117 fragment of a lysozyme analogue

The synthesis of the (105–117) fragment of a Lysozyme analogue is described. This sequence was assembled by DCCl/HONSu fragment coupling of the (105–111) and (112–117) subfragments which were both constructed by the fragment coupling method. The arginine residue at position 114 was initially unprotected but ultimately protection was afforded by the use of the adamantyloxycarbonyl group.     

Peptides—XXXVII: Synthesis of the 1–37 fragment of a lysozyme analogue

Combination of the protected peptide fragments 1–16, 17–26 and 27–37 to yield the 1–37 portion of a lysozyme analogue is described. The fragments were combined using DCCI with the addition of HONSu, and the products purified mainly by gel filtration.     

Peptides—XXXXIII: Synthesis of the 94–104 fragment of a lysozyme analogue

The synthesis of the (94–104) fragment of a lysozyme analogue is reported by union of the protected (94–98) and (99–104) subfragments using the N-hydroxysuccinimide active ester of the (94–98) fragment. This choice of coupling method was made on the basis of a study employing a range of established methods using the criteria of yield and minimum racemisation.     

The lipase of the fungus Rhizopus microsporus,UZLT-1

1. An active lipase enzyme has been isolated from the culture liquid of the fungusRhizopus microsporus, UZLT-1, by precipitation with isopropanol, gel filtration on Sephadexes G-75 and G-150, and chromatography on CM-cellulose. Some properties of the purified enzyme (optimum pH, heat stability, influence of various ions) have been studied.     

Hydrophobic Pocket Modification and Humanized Catalytic Antibodies with Glutathione Peroxidase Activity(Ⅰ)——Preparation and Characterization of Haptenes and Conjugates

ＩｎｔｒｏｄｕｃｔｉｏｎＧｌｕｔａｔｈｉｏｎｅｐｅｒｏｘｉｄａｓｅ（ＧＰＸ）ｆｕｎｃｔｉｏｎｓａｓｏｎｅｏｆａｎｔｉｏｘｉｄａｎｔｄｅｆｅｎｃｅｅｎｚｙｍｅｓｔｏｒｅｄｕｃｅａｗｉｄｅｖａｒｉｅｔｙｏｆｉｎｔｒａｃｅｌｕｌａｒｐｅｒｏｘｉｄｅｓ,ｉｎ...     

A Novel α-Amylase from Bacillus mojavensis A21: Purification and Biochemical Characterization

α-Amylase from Bacillus mojavensis A21 (BMA.2) was purified to homogeneity by ultrafiltration, Sephadex G-75 gel filtration and Sepharose mono Q anion exchange chromatography, with a 15.3-fold increase in specific activity and 11% recovery. The molecular weight of the BMA.2 enzyme was estimated to be 58 kDa by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and gel filtration. The optimum temperature and pH were 80?°C and 6.5, respectively. BMA.2 belonged to the EDTA-sensitive α-amylase, but its activity was not stimulated by the presence of Ca²⁺ ions. The major end-products of starch hydrolysis were maltohexaose, maltopentaose and maltotriose. The N-terminal amino acid sequence of the first ten amino acids of the purified α-amylase was ASVNGTLMQY. Compared to sequences of other amylases, the ten amino acid sequence contains Val at position 3, while amylases from Bacillus licheniformis NH1 and Bacillus sp. SG-1 have Leu and Thr at position 3, respectively.     

The crystal structure of bicyclo [3.3.3]undecane-1,5-diol and the conformation of bicyclo[3.3.3]undecane (manxane)

The crystal structure of bicyclo [3.3.3]undecane-1,5-diol has been determined. It is monoclinic, P2₁/c, a = 12.99(2), b = 14.16(2), c = 12.50(1)A,β = 112.42(2)°, with two independent molecules in the asymmetric unit. One of these is disordered, but the other has almost exact C_3h symmetry and its conformation and precise molecular geometry agree well with previous calculations by molecular mechanics. The molecule shows considerable angle strain, having bridge angles in the range 118–121°     

Purification and characterization of two xylanases from alkalophilic and thermophilic Bacillus licheniformis 77-2

The alkalophilic bacteria Bacillus licheniformis 77-2 produces significant quantities of thermostable cellulase-free xylanases. The crude xylanase was purified to apparent homogeneity by gel filtration (G-75) and ionic exchange chromatography (carboxymethyl sephadex, Q sepharose, and Mono Q), resulting in the isolation of two xylanases. The molecular masses of the enzymes were estimated to be 17 kDa (X-I) and 40 kDa (X-II), as determined by SDS-PAGE. The K _m and V _max values were 1.8 mg/mL and 7.05 U/mg protein (X-I), and 1.05 mg/mL and 9.1 U/mg protein (X-II). The xylanases demonstrated optimum activity at pH 7.0 and 8.0–10.0 for xylanase X-I and X-II, respectively, and, retained more than 75% of hydrolytic activity up to pH 11.0. The purified enzymes were most active at 70 and 75°C for X-I and X-II, respectively, and, retained more than 90% of hydrolytic activity after 1 h of heating at 50°C and 60°C for X-I and X-II, respectively. The predominant products of xylan hydrolysates indicated that these enzymes were endoxylanases.     

Asymmetric acyloin condensation catalysed by phenylpyruvate decarboxylase. Part 2: Substrate specificity and purification of the enzyme

Phenylpyruvate decarboxylase from Achromobacter eurydice was used to catalyse the asymmetric acyloin condensation of phenylpyruvate 1 with various aldehydes 2 to produce optically active acyloins PhCH₂COCH(OH)R 3. The specific activity of the phenylpyruvate decarboxylase enzyme was increased by a factor of 332 after its purification. The molecular weight of the purified enzyme was shown to be 150 kDa by gel filtration chromatography, while SDS gel electrophoresis showed two sub-units with molecular weights of 90 and 40 kDa. The acyloin condensation yield decreased with increasing chain length for straight chain aliphatic aldehydes from 76% for acetaldehyde to 24% for valeraldehyde. The e.e.s of the acyloin products were 87–98%. Low yields of acyloin products were obtained with chloroacetaldehyde (13%) and glycoaldehyde (16%). Indole-3-pyruvate was a substrate of the enzyme and provided acyloin condensation product 3-hydroxy-1-(3-indolyl)-2-butanone 5 with acetaldehyde in 19% yield, while benzoylformate was not a substrate for the enzyme.     

Bioinspired synthesis,characterization and antifungal activity of enzyme-mediated gold nanoparticles using a fungal oxidoreductase

The development of efficient cell-free systems of nanoparticle synthesis using microbial enzymes is a growing field of biological and green chemistry for the supportable improvement in nano-biotechnology. In the present study, we established a cell-free system for producing gold nanoparticles (AuNPs) using a fungal oxidoreductase named sulfite oxidoreductase purified to homogeneity from Fusarium oxysporum. The enzyme was purified by ultrafiltration followed by anion exchange chromatography on DEAE Sephadex A-50 gel, and its molecular weight was determined by gel filtration chromatography on Sephacryl S-300 gel. The purified enzyme had a molecular weight of 346 kDa. It was composed of three subunits of 176, 94 and 76 kDa. Purified enzyme was successfully used for production of gold nanoparticles in a cell-free system. Synthesized gold nanoparticles showed the highest absorbance at 520 nm wavelength as shown by UV–visible spectroscopy. They were spherical in shape with an average size of 20 nm as determined by scanning and transmission electron microscopy and dynamic light scattering. Assessment of the antifungal properties of synthesized nanoparticles by disk diffusion method indicated a potent growth inhibitory activity against all tested human pathogenic yeasts and molds by inhibition zones ranged from 10 to 18 mm. Taken together, our enzymatically established method of nanoparticle synthesis using a purified sulfite oxidoreductase of F. oxysporum can be considered as an efficient tool for generating harmless bioactive gold nanoparticles with potential applications in biology, medicine and industry.     

Purification and Characterization of Three Galactose Specific Lectins from Sajna (Moringa Oleifera L.) Leaves

Three lectins designated as SLL‐1, SLL‐2 and SLL‐3 were purified from small sized Sajna (Moringa oleifera L.) leaves by gel filtration of 100% ammonium sulfate saturated crude protein extract on Sephadex G‐75 followed by ion‐exchange chromatography on DEAE and affinity chromatography on Sepharose‐4B. The molecular weight of the lectins SLL‐1, SLL‐2 and SLL‐3 were 1,55,000, 1,15,000 and 85,000, respectively, as determined by gel filtration on Sephadex G‐150 and 1,60,000; 1,20,000 and 85,500, respectively, by SDS‐polyacrylamide slab gel electrophoresis. SLL‐1 and SLL‐2 are dimer in nature held together by disulfide bond (s), while SLL‐3 is a monomer. The lectins agglutinated specifically rat red blood cells and the agglutination was inhibited specifically by methyl‐α‐D‐galactopyranoside, methyl‐β‐D‐galactopyranoside and D‐galactose. The lectins SLL‐1, SLL‐2 and SLL‐3 contain 3.9, 3.4 and 2.8% neutral sugar, respectively, and the sugar compositions were glucose for SLL‐1, mannose for SLL‐2 and SLL‐3 contained either N‐acetyl‐D‐glucosamine or N‐acetyl‐D‐galactosamine or both. The lectins exhibited cytotoxicity in brine shrimp lethality bioassay.     

Brown Kidney Bean Bowman–Birk Trypsin Inhibitor is Heat and pH Stable and Exhibits Anti-proliferative Activity

A trypsin inhibitor with a molecular mass around 17 kDa was purified from the seeds of Phaseolus vulgaris cv. ‘brown kidney bean’. The purification protocol involved, in sequence, affinity chromatography on Affi-gel blue gel, ion-exchange chromatography on Q-Sepharose and Mono Q, and gel filtration on Superdex 75. The molecular size and N-terminal amino acid sequence of the trypsin inhibitor resembled leguminous Bowman–Birk protease inhibitors (BBIs), signifying that brown kidney bean trypsin inhibitor is a BBI. Brown kidney bean trypsin inhibitor exhibited pronounced thermostability and pH stability. Its trypsin inhibitory activity was retained at all pH values (0–14) and up to 90 °C. The trypsin inhibitor also inhibited the proliferation of human breast cancer MCF7 cells with an IC₅₀ of 71.52 μM. On the other hand, it only slightly inhibited proliferation of hepatoma HepG2 and embryonic liver WRL68 cells at a concentration over 110 μM.     

兽疫链球菌变异株产生的透明质酸的纯化及表征

用N-甲基-N′-硝基-N-亚硝基胍(NTG)对兽疫链球菌进行诱变,获得高产菌株.经过对该菌株的发酵培养,将产生的多糖经Savage法、季铵复合物沉淀法、DEAE-纤维素(DE52)离子交换层析法及SephadexG-75凝胶过滤法分离纯化.纯化的多糖结构经化学组成分析、核磁共振波谱、红外光谱及圆二色谱鉴定,证明了诱变得到的高产菌株(StreptococcuszooepidemicusJ18)再经发酵,得到的多糖为透明质酸.通过刚果红实验证明了透明质酸的构象为单股螺旋结构,其平均分子量约为1.16×10⁶.     

长白山白眉蝮蛇蛇毒精氨酸酯酶1的研究Ⅰ.纯化、分子量测定及纯度鉴定

利用离子交换 (DEAESephadexA - 50 )和凝胶过滤层析 (SephadexG - 75)技术首次从长白山白眉蝮蛇蛇毒 (AgkistrodonblomhoffiiUssurensis)中纯化得到了一种精氨酸酯酶纯品。经SDS -聚丙烯酰胺凝胶电泳(SDS -PAGE)以及基质辅助激光解吸电离飞行时间质谱 (MALDI/TOF/MS)鉴定为单一纯蛋白 ,分子量为2 991 8.5± 1 5Da ,为进一步研究其结构与功能提供了可靠的依据。     

Presence of the basement membrane component--heparan sulfate proteoglycan--in bovine lens capsules

Heparan sulfate proteoglycan was extracted from bovine lens capsules by 0.45 M NaCl/2 M urea and purified using ion-exchange chromatography and gel filtration. The proteoglycan was found to consist of protein and carbohydrate in a ratio of 75 to 25. The estimated average molecular weight of the heparan sulfate proteoglycan eluted by 0.2 M NaCl on a diethylaminoethyl (DEAE)-cellulose column was 400 kilodaltons (kDa) and that of its glycosaminoglycan was 18.8 kDa. The amino acid composition of the proteoglycan was quite similar to that of the bovine glomelular basement membrane.     

The lipase of the fungus Rhizopus microsporus, UZLT-1

Summary 1. An active lipase enzyme has been isolated from the culture liquid of the fungusRhizopus microsporus, UZLT-1, by precipitation with isopropanol, gel filtration on Sephadexes G-75 and G-150, and chromatography on CM-cellulose. Some properties of the purified enzyme (optimum pH, heat stability, influence of various ions) have been studied.Department of Microbiology, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 636–639, September–October, 1976.