Lupin plant

AiTKEN s M, ATTUCCi s, IBRAHIM R K. and GULIK p J (1995) A cDNA encoding geranylgeranyl pyrophosphate synthase from white lupin . Plant Physiol, 108, 837-8. 

Alkaloid concentrations in the plant are in the same order or even higher than the inhibitory concentrations against pathogens that have been established experimentally. Alkaloid-free lupins are highly susceptible to herbivore predation, which shows that the alkaloids are obviously important for the survival of a lupin plant. 

Site of alkaloid formation, transport, and accumulation. QA are formed in the aerial green parts of legumes, especially in the leaves (.9) In lupin leaves we succeeded in localizing the key enzymes of QA biosynthesis in the chloroplast (10, 11), where the formation of the precursor lysine also takes place. Like most of the processes that are located in the chloroplast, QA biosynthesis is regulated by light (.8) and QA formation fol lows a light-dependent diurnal rhythm (, 13). The alkaloids formed in the leaves are translocated via the phloem (13, 14) all over a lupin plant, so that all plant parts contain alkaloids. QA are accumulated and stored preferentially in epidermal and subepidermal tissues of stems and leaves (15, 16). Especially rich in alkaloids are the seeds, which may contain up to 5% (dry weight) alkaloid (equivalent to 200 mmol/ kg). ... 

Primary metabolism. Having briefly reviewed the physiology and biochemistry of QA in the sections above, we can consider the question as to why do lupins produce alkaloids. First of all we can ask whether the QA may play a role in the primary metabolism of a lupin plant. 

All these data support the idea that QA may function as chemical defense compounds. We also tested whether this chemical defense is relevant for the survival of a lupin plant. Lupins offer a unique chance to explore this question experimentally plant breeders have selected "sweet" varieties, which have a very low alkaloid content. These varieties can be compared to semi-bitter or bitter ones. We have grown Lupinus albus strains that differ in their alkaloid content in our experimental garden and greenhouse and have monitored their susceptibility to attack by plant pests. As can be seen from Figure 2, "sweet" lupins are preferentially eaten by rabbits (Cuniculus europaeus) or are infested by aphids (Aphidae) or leaf miners (Agromyzidae). Literature data also support the assumption that alkaloid-rich lupins are much more resistant to plant pests than "sweet" varieties (30-32). We conclude therefore, that QA are indeed important for the fitness of a lupin plant and that they constitute a major part of its chemical defense system, in which... 

Infestation of young lupin plants (greenhouse experiments) by Agromyzidae. About 50-1CX3 plants each were evaluated. 

This is a non-chemical, and probably the first biological, method of determining the presence of alkaloids. It was first used particularly with quinolizidine alkaloids in lupine plants. The tasters were men or animals, even in ancient times. It is based on the fact that quinolizidine alkaloid has a bitter taste. This method is qualitative. Taste is a subjective and individual category, especially in the... 

An extract taken from the composted straw of the alkaloid-rich lupin plants has produced very promising results in the development of biological control agents. The fungistatic activity of straw compost extracts increased markedly when the lupin straw used for composting was enriched with alkaloid extract. 

Phomopsis leptostromiformis occurs in nature as a parasite and saprophyte of certain lupin plants, which are in turn associated with the animal disease lupinosis, a hepatotoxic condition characterized by severe liver damage and jaundice. Field outbreaks of lupinosis have been reported in grazing sheep, cattle, horses and pigs in Europe, Australia, New Zealand and South Africa where lupins are cultivated extensively for livestock feeding. Phomopsin A (11) and several other related metabolites are produced by P. leptostromiformis, in cultures grown on lupin seeds, liquid media or maize kernels. ... 

In vitro tissue and cell cultures of lupin plants are not appropriate systems for the study of biosynthesis of lupin alkaloids, because the production ability by in vitro culture is rather low, i.e., 10 2 to lO times compared with that of differentiated plants. The production of the alkaloids of lupinine- and sparteine-groups by cell culture have been reported by us [59] and by Wink s group [60]. We have also successfully produced matrine in green callus culture and in multiple shoots of Sophora flavescens [61]. The producibility of matrine was positively correlated with the chloroplast formation. This indicates that the formation of carbon skeleton of matrine-type alkaloids also likely takes place in chloroplasts in plant cells as postulated in that of sparteine-type alkaloids [62]. 

Table III Distribution of acyltransferase activities and ester alkaloids in lupin plants.

Chemotaxonomy and phylogenic relations of lupin plants based on structure and distribution of alkaloids... 

Forty four alkaloids were newly isolated from the 22 lupin plants and the structures were elucidated in our recent study. The structures were determined by spectroscopic investigations, in particular, by extensive 2D-NMR experiments in the recent works, and by chemical transformation. Biosynthetic pathways are also proposed, in some cases, by the preparation of isolated enzymes and by in vitro cell culture system. Chemotaxonomic relationships of the lupin plants are discussed based on the structural classification of alkaloids. 

Miller, S.S., Liu, J.Q., Allan, D.L., Menzhuber, C.J., Fedorova, M. and Vance, C.P. (2001) Molecular control of acid phosphatase secretion into the rhizosphere of proteoid roots from phosphorus-stressed white lupin. Plant Physiology 127, 594-606. 

Lupin seeds are produced in pods that develop on the main stem of the lupin plant. The seeds of white lupin are 8 to 14 mm in diameter, flattened, and of cream color. Blue lupins have beige or brown-speckled round and relatively light seeds, whereas yellow lupin seeds are round and resemble soybeans (Figure 22.2). 

The U-NT metabolites in bark and podwalls were transient — that is they were present only during [9R]Z uptake and immediately afterwards [2], When (diH) [9R]Z was supplied to de-rooted lupin plants via the transpiration stream, a transient polar metabolite was again detected in the bark tissues. This metabolite exhibited normal phase TLC properties identical to those of U-NT both compounds exhibited Rf values which were greater than those of Z nucleotide and similar to those of iP nucleotide. Hence this metabolite of (diH)[9R]Z, termed DU-NT henceforth, and U-NT were presumably analogous. 

In blue lupin, a rapid lateral movement of pH]-[9R]Z and [ H]-(diH)(9R]Z from xylem to bark was observed using girdled stems with leaves removed. This movement was somewhat more pronounced in the two main lateral stems which develop just below the primary inflorescence. Thus, when pM]-[9R]Z (2 /xM) was supplied to derooted plants via the xylem stream, for 1.5 h followed by a water chase for 3.5 h, 24% of the total [ H] extracted from the stem was derived from the bark. Kinetic studies of metabolites in xylem plus pith and in bark following pH]-[9R]Z and [ H]-(diH)[9R]Z uptake through the xylem of de-rooted lupin plants, together with studies of the metabolism of these ribosides in excised stem tissues, indicated that (1) the supplied ribosides were translocated to bark per se and possibly as the nucleotides (2) U-Ri and DU-Ri were formed exclusively in the bark and were probably the precursors of U-NT and DU-NT, respectively (3) ribose cleavage and sidechain reduction were largely confined to bark. 

Differences in Biosynthesis in Alkaloid-PoOT and Alkaloid-Rich Lupin Plants 389... 

Also the alkaloid profile is very different seeds of L. aschenbornii contain mainly A -formylangustifohne, whereas stems, leaves and flowers contain mainly sparteine. The explanations proposed by the authors for this diversity are (1) one predator, one organ, that is a variability of QAs can confer to lupin plants higher possibility to survive and reproduce in an adverse environment and (2) the transport of QAs through the plant is uneven [52]. 

Figure 4.3. Schematic distribution of alkaloids in a lupine plant according to Miro-nenko (1965). The concentration of black corresponds to the concentration of alkaloids. Only the youngest plants are alkaloid-rich in older plants a decrease of alkaloids occurs.

Figure 5.6. Appearance of yellow lupine plants (Lupinus luteus) used in experiments 21 days after infection. Left— healthy right—infected (Nowacki and Waller, 1973). Courtesy of the journal.

Figure 5.8c. Example of a displaced insect caterpillar of a European butterfly feeding on a bitter American lupine plant in the lupine collection in Poznan, Poland.

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