Characterization of a novel bioemulsifier from Pseudomonas stutzeri.

This study describes a novel and efficient alasan-like bioemulsifier produced by Pseudomonas stutzeri NJtech 11-1, which was isolated from the Shengli Oilfield. The strain was found to produce a new and interesting emulsion stabilizer. The crude bioemulsifier showed super stability with 50% salinity and broad pH 3-10. The emulsion index (EI24) was increased to 100% after heating from 45 to 95 °C and the emulsion could be stable for at least 30 days. The yield of Ps-bioemulsifier (pure bioemulsifier) was 0.68 ± 0.05 mg mL-1. The Ps-bioemulsifier was composed of carbohydrates (80 ± 2.6%) and proteins (9.5 ± 0.5%). A low concentration (0.2 mg mL-1) of the Ps-bioemulsifier was obtained maximum emulsifying activity at pH 7.1 and its emulsifying activity strengthened by suitable salinity. Furthermore, Ps-bioemulsifier could also emulsify cyclohexane, hexadecane, kerosene, xylene hydrocarbons efficiently. Therefore, the Ps-bioemulsifier showed emulsifying characteristics which make it a good candidate for potential applications in bioremediation and microbial enhanced oil recovery.

DNA vaccine expressing repeated carcinoembryonic antigen (CEA)(625-667) induces strong immunity in mice.

The efficacy of immunization with DNA plasmids for single truncated carcinoembryonic antigen (CEA) peptide or triple repeated CEA peptides in mice was evaluated. A DNA fragment the truncated CEA gene (nucleotide 625-667) encoding two helper T lymphocyte (HTL) epitopes was amplified by PCR and cloned for generating recombinant plasmids for single CEA(625-667) (pcDNA-CEA(625-667)) or triple CEA(625-667) (pcDNA-triCEA(625-667)), respectively. Subsequently, groups of BALB/c female mice were intramuscularly injected with pcDNA-CEA(625-667,) pcDNA-triCEA(625-667) or control pcDNA3.0 vector, respectively. Ten days after the last immunization, the frequency of splenic CD4(+) and CD8(+) T cells in the mice was determined by flow cytometry. The antigen-specific proliferation of splenic T cells and cytokine production ex vivo were analyzed by (3)H-TdR uptake and cytokine ELISA, respectively. The levels of serum antibodies against CEA in the mice were detected by Western blot and ELISA. Although immunization with plasmid for the CEA(625-667) peptide(s) did not alter the frequency of CD4(+) and CD8(+) T cells in mice, vaccination with plasmid for CEA peptide induced strong antigen-specific T cell proliferation, particularly for the plasmid encoding the triple-repeated CEA peptides, accompanied by significantly elevated levels of IFN-γ secreted by T cells from the mice immunized with triple-repeated peptides. Furthermore, immunization with the plasmid for CEA peptide stimulated higher levels of antigen-specific antibody responses in mice. Vaccination with the plasmid for the triple repeated CEA peptides induced stronger Th1 responses. Our findings may be useful for the development of effective DNA vaccine for the immunotherapy of cancer.

2-[(E)-(Dimethyl-amino)methyl-ene-amino]benzonitrile.

In the title compound, C(10)H(11)N(3), the amidine unit, including the two methyl substituents, is virtually planar [maximum deviation = 0.016 (5) Å]. The plane of the benzene ring forms a dihedral angle of 46.5 (3)° with the amidine group.

2,2,7-Trimethyl-2,3-dihydro-quinazolin-4(1H)-one.

There are two independent mol-ecules in the the asymmetric unit of the title compound, C(11)H(14)N(2)O. The heterocyclic ring of the bicyclic system has a sofa conformation, with the C atom bearing the two methyl groups displaced by 0.541 (7) Šfrom the rest of the atoms of the ring [planar to within 0.064 (9) Å]. Mol-ecules are linked into centrosymmetric dimers via N-H⋯O hydrogen bonds.

(S)-2-(3-Nitro-phen-yl)-1,2-dihydro-quinazolin-4(3H)-one.

In the racemic title compound, C(14)H(11)N(3)O(3), the pyrimidine ring has an envelope conformation with the puckering parameters Q = 0.3338 (17) Å, Θ = 60.1 (3) and ϕ = 290.4 (3)°. The two N-H groups form hydrogen bonds with symmetry-related mol-ecules, building a two-dimensional network parallel to the (10) plane.

1-Phenyl-6,7,8,9-hexa-hydro-1H,5H-cyclo-hepta-[1',2':2,3]pyrido[6,5-c]pyrazol-4-amine: a new tacrine analogue.

The title compound, C(17)H(18)N(4), contains a pyrazolopyridine system fused with a seven-membered carbocyclic ring. The pyrazole ring is coplanar with the pyridine ring, while the phenyl ring is twisted by a dihedral angle of 14.38 (14)° with respect to the pyridine ring. The seven-membered ring displays a chair conformation. The packing is stabilized by N-H⋯N hydrogen bonds and N-H⋯π(arene) inter-actions.