RESUMEN
A Bombyx mori L. (Lepidoptera: Bombycidae) gene encoding tryptophan oxygenase has been molecularly cloned and analyzed. The tryptophan oxygenase cDNA had 1374 nucleotides that encoded a 401 amino acid protein with an estimated molecular mass of 46.47 kDa and a PI of 5.88. RT-PCR analysis showed that the B. mori tryptophan oxygenase gene was transcribed in all examined stages. Tryptophan oxygenase proteins are relatively well conserved among different orders of arthropods.
Asunto(s)
Bombyx/enzimología , Bombyx/genética , Triptófano Oxigenasa/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Bombyx/clasificación , Clonación Molecular , Perfilación de la Expresión Génica , Regulación Enzimológica de la Expresión Génica , Datos de Secuencia Molecular , Filogenia , Estructura Secundaria de Proteína , Alineación de Secuencia , Triptófano Oxigenasa/químicaRESUMEN
<p><b>OBJECTIVE</b>To investigate the antibacterial effect of a particular antimicrobial peptide Cecropin B(CB) on Pseudomonas aeruginosa infection of wound in mice.</p><p><b>METHODS</b>Thirty ICR mice were enrolled in the study, and the Pseudomonas aeruginosa infection model was reproduced by excision of the full layer of dorsal skin with an area of 1 cm x 1 cm. Then they were randomly divided into C ( control, n = 10, with wet compress of isotonic saline at 3 postinjury hour( PIH) ) , M (with hydropathic compress of 100 g/L mafenide at 3 PIH), A (with wet compress of 1 000 mg/L Cecropin B at 3 PIH) groups. The changes in body temperature and hemogram in each group were determined before and 4 days after injury. Quantitative examination were used to detect the quantity of bacteria in muscular tissue of the wounds, and the survival of the mice were observed on 4 post-injury day( PID).</p><p><b>RESULTS</b>The wounds were moist with more exudation in C group,while that in other groups were dry without obvious exudation. The body temperature of the majority of the mice in each group were elevated, but the number of leucocytes in each group was lowered after operation. The quantity of bacteria in muscle in A group[ (42 +/- 50) CFU/g] was obviously lower than that in M group [(886+/-804) CFU/g, P <0.05] , and it was all obviously lower than that in C group[ (41 +/-28) x 10(5) CFU/g, P <0.01]. The number of surviving mice after 4 PID in C group was evidently smaller than that in A and M groups( P <0. 05).</p><p><b>CONCLUSION</b>The cecropin B possesses obvious anti-bacterial effect on the Pseudomonas Aeruginosa infected wounds of ICR mice, and it can reduce the mortality.</p>
Asunto(s)
Animales , Masculino , Ratones , Péptidos Catiónicos Antimicrobianos , Usos Terapéuticos , Modelos Animales de Enfermedad , Proteínas de Insectos , Usos Terapéuticos , Ratones Endogámicos ICR , Infecciones por Pseudomonas , Quimioterapia , Infección de Heridas , Quimioterapia , MicrobiologíaRESUMEN
A 44-residue hybrid peptide (CB (1-24)-Arg-Ser-Tyr-Tan (4-21)) incorporating 1-24 residues of cecropin B (CB) and 4-21 residues of thanatin (Tan) was designed and constructed. The CB-Tan gene was cloned into expression plasmid pGEX-3X and expressed in E. coli BL21. The fusion protein was purified by affinity chromatography. After digested with enterokinase the gene product released with antibacterial activity and gave one band in Tricine-SDS-PAGE.