Production of Mevalonic Acid by Fermentation

The purpose of this investigation was to select microorganisms that produce substantial quantities of mevalonic acid and to develop an economic fermentation process. To screen for mevalonic acid-producing microorganisms, it was necessary to improve the method for the quantitative determination of this acid. The biological assay was modified by shortening the incubation time and simplifying the procedure. The principle of the assay is based on the essential mevalonic acid requirement of the organism Lactobacillus heterohiochii for growth. Screening was carried out by selecting high mevalonic acid-producing organisms from various type cultures. Endomycopsis fibuliger was chosen for medium development studies, and 939 mug of mevalonic acid per ml was produced in the culture filtrate after modifications of medium and fermentation conditions.     

Restriction and modification in Bacillus species: genetic transformation of bacteria with DNA from different species, part I.

Summary Host specific restriction was detected in 13 Bacillus strains, when 63 strains of Bacillus subtilis and 15 other Bacillus strains were tested with phage 105C. These 13 strains were classified into 8 groups (M,H,C,N,E,F,G,P) by the type of restriction. M-type strains (B. subtilis Marburg 168, its derivatives, and two other strains) showed relatively weak restriction, restricting 105C from other groups of Bacillus by ratios of 10^-1 to 10^-3. Strains of groups H,C,N,E,F,G, and P restricted 105C from other groups by ratios of 10^-2 to 10^-8. It was confirmed with some of the strains that type-specific modification was endowed only by the last host. Furthermore, we isolated one restriction deficient mutant of B. subtilis marburg 168-YS11, which had also lost its modification phenotype.     

Purification of cohesive-end-producing restriction endonuclease from Bacillus subtilis G.

A new restriction endonuclease was partially purified from Bacillus subtilis G (IAM1247). This restriction endonuclease (endonuclease RBsuG) seems to produce cohesive ends at its cleavage site.     

Spin-state exchange in fusarium lipoxygenase on binding of linoleic acid.

The electron paramagnetic resonance(EPR) signals of Fusarium lipoxygenase were measured at liquid nitrogen temperature in the presence or absence of substrate, linoleic acid. The spin-state exchange of heme iron in Fusarium lipoxygenase from a low to high spin-state by the addition of linoleic acid was observed. The addition of linoleic acid to the enzyme at pH 9.0 gave rise to the appearance of EPR lines at g=5.92 and 3.58, while at pH 12.0, lines at g=6.12 and 3.41 were newly appeared. At the same time, the resonance at g=4.31 was increased both at pH 9.0 and 12.0 in the presence of linoleic acid.     

Steroidal plant growth regulators,castasterone and typhasterol (2-deoxycastasterone) from the shoots of sitka spruce (Picea sitchensis)

Castasterone, [(22R,23R,24S)-2α,3α,22,23-tetrahydroxy-24-methyl-5α-cholestan-6-one] and typhasterol (2-deoxycastasterone) have been identified in purified extracts from the shoots of Sitka spruce (Picea sitchensis) by GC/MS.     

Partial characterization of an unusual 185 kDa protein synthesized by dermal fibroblasts from patients with Marfan syndrome: identification of the protein as type IV collagen

Production of an unusual collagenous protein was observed in culture of dermal fibroblasts from four patients with Marfan syndrome. The apparent molecular weight of the protein was about 185 kDa after reduction with 2-mercaptoethanol and 175 kDa after limited pepsin treatment. The 185 kDa protein was susceptible to the bacterial collagenase but resistant to the animal collagenase. Immunoprecipitation revealed the specific interaction of the pepsin-treated 175 kDa collagenous protein with monoclonal and polyclonal antibodies to human type IV collagen. From the patterns of CNBr peptide mapping the 185 kDa band was identified as alpha 1 (IV) chain. Type IV collagen in the skin is generally considered to be of non-fibroblastic origin. However, in "diseased" condition, dermal fibroblasts might produce type IV collagen. The clinical manifestation in relation to production of type IV collagen by cultured skin fibroblasts from Marfan patients is discussed.     

Prostaglandin D2 receptors DP and CRTH2 in the pathogenesis of asthma

Prostaglandin D2 (PGD2) is a major prostanoid produced mainly by mast cells in allergic diseases, including bronchial asthma. However, its role in the pathogenesis of asthma remains unclear. PGD2-induced vasodilatation and increased permeability are well-known classical effects that may facilitate transendothelial migration of inflammatory cells, such as eosinophils, mast cells, lymphocytes, and monocytes in allergic inflammation. These effects are initiated via a PGD2 receptor, D prostanoid receptor (DP), and are referred to as DP-mediated vasodilation-extravasation. Recently, novel functions of DP have been identified. Furthermore, a novel and different receptor of PGD2, CRTH2, has been discovered. To date, DP and CRTH2 have been shown to be major PGD(2)-related receptors that have pivotal roles in mediating allergic diseases by effects such as directly regulating the migration of inflammatory cells and controlling the production of cytokines and lipid mediators. Available evidence suggests that CRTH2 and DP may collaborate in allergic inflammation. This review focuses on the novel roles of DP and CRTH2 in the initiation and maintenance of allergy.     

Efficient in vitro germination and shoot proliferation of chilling-treated water chestnut (Trapa japonica Flerov) embryonal explants

Summary Embryonal explants from water chestnut (Trapa japonica Flerov) seeds germinated with high efficiency following a 40-d cold treatment at 5°C on half-strength MS (Murashige and Skoog) medium supplemented with 2.7 μM N⁶-benzyladenine (BA), 0.5 μM 1-naphthaleneacetic acid (NAA) and 0.5 μM gibberellic acid (GA₃). Control and chill-treated (different durations) embryonal explants were cultured onto media which contained half-strength MS medium supplemented with different concentrations and combinations of cytokinins [BA, thidiazuron (TDZ), kinetin, zeatin], auxin (NAA) and GA₃. A liquid half-strength MS medium with 1.1 μM BA and 0.5 μM NAA resulted in the best shoot proliferation of control or chill-treated explants, and the addition of 0.5 μM GA₃ stimulated axillary shoot elongation. Germination and shoot proliferation were always greater for chill-treated explants compared with control explants under the same culture conditions. Shoots produced in vitro rooted 100% of the time in a liquid half-strength MS medium with 1.1 μM BA, 0.5 μM NAA and 1.1 μM indole-3-butyric acid, and the regenerated plantlets were established successfully in a water chestnut paddy field.