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The purpose of the study was to evaluate the possible genetic effect on vegetative propagation of Coffea canephora. Diversity for somatic embryogenesis (SE) ability was observed not only among two groups of C. canephora Pierre (Congolese and Guinean), but also within these different genetic groups. The results therefore showed that, under given experimental conditions, SE ability is depending on genotype. Furthermore the detection of quantitative trait loci (QTLs) controlling the SE and cutting abilities of C. canephora was performed on a large number of clones including accessions from a core collection, three parental clones and their segregating progenies. On the one hand we detected eight QTLs determining SE. Six positive QTLs for SE ability, whatever the criteria used to quantify this ability, were localized on one single chromosome region of the consensus genetic map. Two negative QTLs for SE ability (frequency of micro calli without somatic embryo) were detected on another linkage group. Deep analysis of the six QTLs detected for SE ability came to the conclusion that they can be assimilated to one single QTL explaining 8.6-12.2% of the observed variation. On the other hand, two QTLs for average length of roots and length of the longest sprouts of cuttings were detected in two linkage groups. These QTLs detected for cutting ability are explaining 12-27% of the observed variation. These observations led to conclude that SE and cutting abilities of C. canephora Pierre appeared to be genetic dependent but through independent mechanisms.

Until recently breeding efforts centred on high-yield production while sacrificing flavour and taste quality traits of mass produced food products, such as tomatoes. The recent publication of Davidovich-Rikanati et al. demonstrates the technical feasibility of the genetical engineering of pathways in tomato plants to modify their fruit flavour profile in a proof-of-concept approach. The reported work ranks among an increasing number of reported successful modifications of edible plants with a focus on the benefits to end-consumers.

The present article describes two novel flexible plastic-based disposable bioreactors. The first one, the WU bioreactor, is based on the principle of a wave and undertow mechanism that provides agitation while offering convenient mixing and aeration to the plant cell culture contained within the bioreactor. The second one is a high aspect ratio bubble column bioreactor, where agitation and aeration are achieved through the intermittent generation of large diameter bubbles, "Taylor-like" or "slug bubbles" (SB bioreactor). It allows an easy volume increase from a few liters to larger volumes up to several hundred liters with the use of multiple units. The cultivation of tobacco and soya cells producing isoflavones is described up to 70 and 100 L working volume for the SB bioreactor and WU bioreactor, respectively. The bioreactors being disposable and pre-sterilized before use, cleaning, sterilization, and maintenance operations are strongly reduced or eliminated. Both bioreactors represent efficient and low cost cell culture systems, applicable to various cell cultures at small and medium scale, complementary to traditional stainless-steel bioreactors., ((c) 2006 Wiley Periodicals, Inc.)

We report herein the application of a set of algorithms to identify a large number (2869) of single-copy orthologs (COSII), which are shared by most, if not all, euasterid plant species as well as the model species Arabidopsis. Alignments of the orthologous sequences across multiple species enabled the design of "universal PCR primers," which can be used to amplify the corresponding orthologs from a broad range of taxa, including those lacking any sequence databases. Functional annotation revealed that these conserved, single-copy orthologs encode a higher-than-expected frequency of proteins transported and utilized in organelles and a paucity of proteins associated with cell walls, protein kinases, transcription factors, and signal transduction. The enabling power of this new ortholog resource was demonstrated in phylogenetic studies, as well as in comparative mapping across the plant families tomato (family Solanaceae) and coffee (family Rubiaceae). The combined results of these studies provide compelling evidence that (1) the ancestral species that gave rise to the core euasterid families Solanaceae and Rubiaceae had a basic chromosome number of x=11 or 12.2) No whole-genome duplication event (i.e., polyploidization) occurred immediately prior to or after the radiation of either Solanaceae or Rubiaceae as has been recently suggested.

A Nicotiana tabacum cv. Xanthi cell culture was initiated from a transgenic plant expressing a human anti-rabies virus monoclonal antibody. Within 3 months, plant cell suspension cultures were established and recombinant protein expression was examined. The antibody was stably produced during culture growth. ELISA, protein G purification, Western blotting, and neutralization assay confirmed that the antibody was fully processed, with association of light and heavy-chains, and that it was able to bind and neutralize rabies virus. Quantification of antibody production in plant cell suspension culture revealed 30 microg/g of cell dry weight for the highest-producing culture (0.5 mg/L), 3 times higher than from the original transgenic plant. The same production level was observed 3 months after cell culture initiation. Plant cell suspension cultures were successfully grown in a new disposable plastic bioreactor, with a growth rate and production level similar to that of cultures in Erlenmeyer flasks.

An EST database has been generated for coffee based on sequences from approximately 47,000 cDNA clones derived from five different stages/tissues, with a special focus on developing seeds. When computationally assembled, these sequences correspond to 13,175 unigenes, which were analyzed with respect to functional annotation, expression profile and evolution. Compared with Arabidopsis, the coffee unigenes encode a higher proportion of proteins related to protein modification/turnover and metabolism-an observation that may explain the high diversity of metabolites found in coffee and related species. Several gene families were found to be either expanded or unique to coffee when compared with Arabidopsis. A high proportion of these families encode proteins assigned to functions related to disease resistance. Such families may have expanded and evolved rapidly under the intense pathogen pressure experienced by a tropical, perennial species like coffee. Finally, the coffee gene repertoire was compared with that of Arabidopsis and Solanaceous species (e.g. tomato). Unlike Arabidopsis, tomato has a nearly perfect gene-for-gene match with coffee. These results are consistent with the facts that coffee and tomato have a similar genome size, chromosome karyotype (tomato, n=12; coffee n=11) and chromosome architecture. Moreover, both belong to the Asterid I clade of dicot plant families. Thus, the biology of coffee (family Rubiacaeae) and tomato (family Solanaceae) may be united into one common network of shared discoveries, resources and information.

Alpha-D-Galactosidase (alpha-Gal; EC 3.2.1.22) is one of three principal enzymes involved in the modification or degradation of plant cell wall galactomannans. In the present paper it is shown that alpha-galactosidase activities in field-grown coffee beans are variable amongst cultivars of the two species investigated (Coffea arabica and C. canephora var. Robusta). Higher activities were found in Arabica cultivars. Using beans from greenhouse-cultivated C. arabica as a model, we showed that alpha-Gal activity was undetectable in the bean perispem tissue, but increased gradually during the endosperm development, to reach a peak at approximately 30 weeks after flowering (WAF) which coincided with the hardening of the endosperm. Alpha-Gal-specific transcripts detected at 22 and 27 WAF accompanied the peak of alpha-Gal activity, but were reduced to be undetectable in mature beans at 30 WAF, while alpha-Gal activity still persisted. Two isoforms were distinguished in 2-DE profiles of crude protein extracts by N-terminal sequencing analysis. Analysis of two-dimensional gel electrophoresis profiles demonstrated that both isoforms accumulated in a linear fashion throughout grain maturation. Alpha-Gal activity was also observed to increase to high levels during in vitro germination of coffee beans suggesting an important function of this enzyme in this process. Alpha-Gal cDNA sequences from Arabica and Robusta were sequenced and their deduced proteins appeared to be very similar, differing by only eight amino acids. Southern-blot analysis suggests that the enzyme was encoded by at least two genes in C. arabica that could explain the existence of the two isoforms identified in 2-DE profiles.

The accumulation of the terpenes ginkgolides and bilobalide in Ginkgo biloba was reported in plants as well as in plant cell cultures. Several hundred plants cultivated under controlled conditions in the field have been analyzed for their terpene production over many years. Cross-pollination experiments were performed with mature trees and the terpene content of the progeny was analyzed. The age of the tree is the main factor influencing the terpene content of the leaves as the level always decreases dramatically between young and old trees. 80 cell culture strains have been established and ginkgolides analyzed by GC/MS. These cell cultures reveal very low amounts of terpenes (1 microgram g-1 D.W. or less). On the contrary, isolated in vitro root cultures accumulate terpenes at the same concentration as the young plant leaves (4 mg g-1 D.W.). Attempts to obtain rapid growing roots or even hairy-roots did not succeed but the possibility to transform Ginkgo cell strains has been demonstrated.

A methodology for flavor and composition assessment of processed tomato juice samples was developed using a wide range of commercial processing tomato varieties (Lycopersicon esculentum) grown in Spain and the United States. Fruitiness intensity was found by a trained panel to best describe overall tomato flavor. For two consecutive years, fruitiness intensity was significantly dependent on growing location and variety, and it was consistently linked to increased levels of glucose and reducing sugars and decreased glutamic acid content. Using the same procedure on a population of 176 breeding lines derived from the wild species of Lycopersicon pimpinellifolium, it was shown that tomato fruitiness intensity was significantly correlated to reducing sugars/glutamic acid ratio and glucose and glutamic acid contents. The definition of markers for tomato flavor of processed juice can provide the tomato breeder and processor with reliable analytical tools that can be applied in a straightforward way for the identification of raw materials that can be processed into juice with predictably high or low fruitiness.