Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.2.1.23 (beta-galactosidase)
 14,648 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In utero injection of cationic liposome-DNA complexes (CLDCs) containing chloramphenicol acetyltransferase, beta-galactosidase (beta-gal), or human granulocyte colony-stimulating factor (hG-CSF) expression plasmids produced high-level gene expression in fetal rats. Tissues adjacent to the injection site exhibited the highest levels of gene expression. Chloramphenicol acetyltransferase expression persisted for at least 14 days and was reexpressed following postnatal reinjection of CLDCs. Intraperitoneal administration of the hG-CSF gene produced high serum hG-CSF levels. X-gal staining demonstrated widespread beta-gal expression in multiple fetal tissues and cell types. No toxic or inflammatory responses were observed, nor was there evidence of fetal-maternal or maternal-fetal gene transfer, suggesting that CLDCs may provide a useful alternative to viral vectors for in utero gene transfer.
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PMID:Fetal gene transfer by transuterine injection of cationic liposome-DNA complexes. 1058 16

The ability of Toxoplasma gondii to cycle between the tachyzoite and bradyzoite life stages in intermediate hosts is key to parasite survival and the pathogenesis of toxoplasmosis. Studies from a number of laboratories indicate that differentiation in T. gondii is a stress-induced phenomenon. The signalling pathways or molecular mechanisms that control formation of the latent bradyzoite stage are unknown and specific effectors of differentiation have not been identified. We engineered a reporter parasite to facilitate simultaneous comparison of differentiation and replication after various treatments. Chloramphenicol acetyltransferase (CAT), expressed constitutively from the alpha-tubulin promoter (TUB1), was used to quantitate parasite number. beta-galactosidase (beta-GAL), expressed from a bradyzoite specific promoter (BAG1), was used as a measure of bradyzoite gene expression. Sodium nitroprusside, a well-known inducer of bradyzoite differentiation, reduced reporter parasite replication and caused bradyzoite differentiation. Stress-induced differentiation in many other pathogens is regulated by cyclic nucleotide kinases. Specific inhibitors of the cAMP dependent protein kinase and apicomplexan cGMP dependent protein kinase inhibited replication and induced differentiation. The beta-GAL/CAT reporter parasite provides a method to quantify and compare agents that cause differentiation in T. gondii.
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PMID:Cyclic nucleotide kinases and tachyzoite-bradyzoite transition in Toxoplasma gondii. 1621 48

In this work the overlapping genes (lacL and lacM) encoding heterodimeric beta-galactosidases from Lactobacillus reuteri , Lb. acidophilus , Lb. sakei , and Lb. plantarum were cloned into two different nisin-controlled expression (NICE) vectors and expressed using Lactococcus lactis NZ9000 and NZ3900 as hosts. The lacL gene, encoding the large subunit of the beta-galactosidases, was fused translationally downstream of the nisin-inducible promoter nisA. Chloramphenicol was employed as selection marker for the standard system using L. lactis NZ9000, whereas lactose utilization based on the complementation of the lacF gene was used as a dominant selection marker for the food-grade system employing L. lactis NZ3900. Comparison of the standard and the food-grade expression system, differing only in their selection markers, gave considerable differences in volumetric beta-galactosidase activity, ranging from 1.17 to 14 kU/L of fermentation broth, depending on both the origin of the lacLM genes and the selection marker used. The occurrence of codons less frequently used by L. lactis especially at the beginning of the lacL gene could be an explanation for the significant differences between the expression levels of lacLM from different origins, while plasmid stability might cause the difference obtained when employing the different selection markers.
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PMID:High-level expression of Lactobacillus beta-galactosidases in Lactococcus lactis using the food-grade, nisin-controlled expression system NICE. 2009 20


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