Preliminary examination of factors affecting Agrobacterium tumefaciens-mediated transformation of marula, Sclerocarya birrea subsp. caffra (Anacardiacease)

In planta Agrobacterium tumefaciens-mediated transformation of marula, Sclerocarya birreasubsp. caffra(Anacardiaceae) resulted in chimeric transgenic in vitro shoots at a rate of 0.8--1.5%. Average transgene expression rates of 33.1 and 1.3% GUS-positive explants were observed on days 3 and 6 after agroinfection, respectively. One to 4 GUS-positive zones were observed per GUS-positive explant section. Addition of acetosyringone (100 μM) during co-cultivation significantly improved transient transformation efficiency as determined by the percentage of GUS-positive explants on day 3 (p< 0.05) whereas wounding did not show a significant effect. However, wounding and acetosyringone acted antagonistically reducing transient transformation rates.     

Preliminary examination of factors affecting Agrobacterium tumefaciens-mediated transformation of marula, Sclerocarya birrea subsp. caffra (Anacardiacease)

In planta Agrobacterium tumefaciens-mediated transformation of marula, Sclerocarya birreasubsp. caffra(Anacardiaceae) resulted in chimeric transgenic in vitro shoots at a rate of 0.8--1.5%. Average transgene expression rates of 33.1 and 1.3% GUS-positive explants were observed on days 3 and 6 after agroinfection, respectively. One to 4 GUS-positive zones were observed per GUS-positive explant section. Addition of acetosyringone (100 M) during co-cultivation significantly improved transient transformation efficiency as determined by the percentage of GUS-positive explants on day 3 (p< 0.05) whereas wounding did not show a significant effect. However, wounding and acetosyringone acted antagonistically reducing transient transformation rates.     

Targeting of Human Antigen-Presenting Cell Subsets

Antigen-presenting cells are a heterogeneous group of cells that are characterized by their functional specialization. Consequently, targeting specific antigen-presenting cell subsets offers opportunities to induce distinct T cell responses. Here we report on the generation and use of nanobodies (Nbs) to target lentivectors specifically to human lymph node-resident myeloid dendritic cells, demonstrating that Nbs represent a powerful tool to redirect lentivectors to human antigen-presenting cell subsets.     

Cloning and Sequencing of the cDNA Encoding the Rubber Elongation Factor of Hevea brasiliensis

In Hevea brasiliensis, the rubber particle in the laticiferous vessel is the site of rubber (cis-1-4-polyisoprene) biosynthesis. A 14 kilodalton protein, rubber elongation factor (REF), is associated with the rubber particle in a ratio of one REF to one rubber molecule (Dennis M, Henzel W, Bell J, Kohr W, Light D [1989] J Biol Chem 264: 18618-18628; Dennis M, Light D [1989] J Biol Chem 264: 18608-18617). To obtain more information concerning the function of REF and its synthesis and assembly in the rubber particle, we isolated cDNA clones encoding REF. We used antibodies to REF to screen a Hevea leaf γgt11 cDNA expression library and obtained several positive clones. Sequence analysis of the REF cDNA clones showed that the REF mRNA contains 121 nucleotides of 5′-nontranslated sequences and a 205 nucleotide 3′-nontranslated region. The open reading frame encodes the entire 14 kilodalton REF protein without any extra amino acids (Dennis M, Henzel W, Bell J, Kohr W, Light D [1989] J Biol Chem 264: 18618-18628). The REF cDNA was subcloned in pGEM-3Z/-4Z and expressed in vitro. The translation product is a 14 kilodalton protein that can be immunoprecipitated with antibodies to REF. Addition of microsomal membranes to the in vitro translation product did not alter the mobility of the REF protein. This, and the sequence data, indicate that REF is not made as a preprotein. Our results suggest that REF is synthesized on free polysomes in the laticifer cytoplasm and that assembly of the rubber particles is likely to occur in the cytosol.     

Production of improved infant porridges from pearl millet using a lactic acid fermentation step and addition of sorghum malt to reduce viscosity of porridges with high protein,energy and solids (30%) content

With the aim of improving the safety and nutritional quality of traditional African weaning porridge, the reduction of the viscosity of a high solids fermented pearl millet porridge by addition of sorghum malt (amylase rich flour, ARF) was investigated. The effect of fermentation, cooking, malt addition and recooking on the microflora of, and the survival of an inoculated pathogen were determined. Addition of 5% (w/v) sorghum ARF to the gelatinized millet porridge gave an acceptable viscosity of 2500–3000 cP at a high solid content of 30%. Fermentation inhibited the growth of microorganisms in the porridge and recooking the fermented porridge after sorghum ARF addition further eliminated (<10² c.f.u./g) the moulds and coliforms that were introduced with the sorghum ARF. The recooked, fermented millet plus sorghum ARF porridge prevented the proliferation of the inoculated Escherichia coli and reduced it to <10² c.f.u./g within 18 h. The porridge could supply children under 3 years with the daily required protein using 1.4 feedings per day and required energy with 4 feedings a day.