ABSTRACr Induction of stress metabolites in the suspension cultured cells of eglant (Solanum melongena L.) was exmine. When autoclaved RNase A or nigeran, both of which are nonspecific phytoalexin elicitors in bean cells, were added to the cell culture of eggplant, greatly enhanced levels of three compounds were observed. One ofthem was cis-pentadeca-6-ene-1,3-diyne-5,15-diol, a novel diacetylenic compound. This compound has considerable futoxic activity. Also identified was falindiol, another fungitoxic diacetylenic compound previously reported as one of the phytoalexins in infected tomato fruits and leaves. Elicited compounds preferentially accumulated in the culture medium rather than in the cells and deceased to oinal levels during prolonged culturing. The elicitation of these compounds was closely correlated with cellular damage in terms of the decrease of growth rate and was inhibited by 10 micromolar cycloheximide. Production oflow-mol antimicrobial stress metabolites knowvn as phytoalexins is a well documented response of plants to infection by microorganisms. Despite the chemical diversity of phytoalexins in the plant kingdom, a general similarity of chemical types within a family has been observed. Plants of the Leguminosae, Solanaceae, Compositae, and Convolvulaceae produce predominantly isoflavonoids, carbocyclic-sesquiterpen-oids, polyacetylenes, and furanosesquiterpenoids, respectively, as characteristic phytoalexins (14). Formation of isoflavonoid-related phytoalexins in leguminous plants and in suspension cultured cells can be stimulated by treatment with various elicitors. The combination of cultured cells and abiotic elicitors, such as autoclaved RNase A, has been shown to be a suitable experimental system for investigating the mechanism of induction of phytoalexin formation in leguminous plants (7, 8). In the case of solanaceous plants, only biotic elicitation of phytoalexins in suspension cultured cells of potato has been examined. Brindle et al. (4) reported the accumulation of ses-quiterpenoid phytoalexins, rishitin, lubimin, and solavetivone, upon inoculation with the fungal pathogen Phytophthora infes-tans. However, subsequent studies by Zacharius and Kalan (22) failed to report such compounds in potato cells responding to infection with the same fungus or fungal elicitors. Sesquiterpen-oid phytoalexins have also been reported from infected fruits of eggplant (19, 21). In addition to the sesquiterpenoid phytoalexins, diacetylenic compounds have been found in tomato fruits and leaves infected with fungi (6). It has not been clearly established whether diace-tylenic compounds are phytoalexins common to solanaceous plants. Thus, it is worthwhile examining whether cultured cells Wakayamadai, Shimamoto-cho, Mishima-gun, of solanaceous plants other than potato produce sesquiterpenoid and/or diacetylenic phytoalexins upon interaction with biotic and/or abiotic elicitors. It is also important to know whether the induction ofthe two different types of phytoalexins are regulated in the same manner....

Intracellular localization of lunularic acid and prelunularic acid in suspension cultured cells of Marchantia polymorpha L. was studied. The sum of both compounds was determined as lunularic acid group (LNAs) because of the instability of prelunularic acid to convert into lunularic acid.Mechanical disruption of the cells followed by differential centrifugation showed that LNAs was associated with the supernatant of 100,OOOg centrifugation. Protoplasts isolated from the cells were osmotically ruptured and the distribution of LNAs among the organelles was examined by discontinuous density gradient centrifugation of the protoplast contents. Successful isolation of intact chloroplasts, mitochondria and peroxisomes free from cytoplasm indicated that LNAs was not accumulated in these organelles. Flotation techniques resulted in an efficient isolation of pure vacuoles and revealed that LNAs was distributed almost equally in the vacuoles and cytoplasm.

Marchantia polymorpha ferredoxin was purified by DE-52 and Sephadex G-75 column chromatographies to homogeneity. The complete amino acid sequence of the carboxymethylated (Cm) ferredoxin was determined by conventional methods to be as follows. Thr-Phe-Lys- Val-Thr-Leu-Asn-Thr-Pro-Thr-Gly-Gln-Ser-Val-Ile-Asp-Val-Glu-Asp- Asp-Glu-Tyr-Ile-Leu-Asp-Ala-Ala-Glu-Glu-Ala-Gly-Leu-Ser-Leu-Pro- Tyr-Ser-Cys-Arg-Ala-Gly-Ala-Cys-Ser-Ser-Cys-Ala-Gly-Lys-Val-Thr- Ala-Gly-Glu-Val-Asp-Gln-Ser-Asp-Glu-Ser-Phe-Leu-Asp-Asp-Asp-Gln- Met-Asp-Glu-Gly-Tyr-Val-Leu-Thr-Cys-Ile-Ala-Tyr-Pro-Thr-Ser-Asp- Leu-Thr-Ile-Asp-Thr-His-Gln-Glu-Glu-Ala-Leu-Ile. The total number of amino acid residues was 95 and the molecular weight was calculated to be 10,174, excluding iron and sulfur atoms. The distribution of the four cysteine residues chelating the two iron atoms was identical to those of other [2Fe-2S] ferredoxins. The relationship between M. polymorpha and other plants was discussed in terms of plant phylogeny.

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