Manipulation of IME4 expression, a global regulation strategy for metabolic engineering in Saccharomyces cerevisiae

Metabolic engineering has been widely used for production of natural medicinal molecules. However, engineering high-yield platforms is hindered in large part by limited knowledge of complex regulatory machinery of metabolic network. N6-Methyladenosine (m6A) modification of RNA plays critical roles in regulation of gene expression. Herein, we identify 1470 putatively m6A peaks within 1151 genes from the haploid Saccharomyces cerevisiae strain. Among them, the transcript levels of 94 genes falling into the pathways which are frequently optimized for chemical production, are remarkably altered upon overexpression of IME4 (the yeast m6A methyltransferase). In particular, IME4 overexpression elevates the mRNA levels of the methylated genes in the glycolysis, acetyl-CoA synthesis and shikimate/aromatic amino acid synthesis modules. Furthermore, ACS1 and ADH2, two key genes responsible for acetyl-CoA synthesis, are induced by IME4 overexpression in a transcription factor-mediated manner. Finally, we show IME4 overexpression can significantly increase the titers of isoprenoids and aromatic compounds. Manipulation of m6A therefore adds a new layer of metabolic regulatory machinery and may be broadly used in bioproduction of various medicinal molecules of terpenoid and phenol classes.

Limonoids from seeds of A. Juss. and their cytotoxic activity

Four new limonoid-type nortriterpenoids, 1-detigloyl-1--methacryloylsalannin (), 28-deoxo-2,3-dihydronimbolide (), 12-acetoxy-3--acetyl-7--tigloylvilasinin () and 12-acetoxy-3--acetyl-7--methacryloylvilasinin (), along with five known ones, were isolated from seeds of A. Juss. Their structures were elucidated by various spectroscopic methods, including UV, IR, MS, NMR, X-ray crystallography, quantum chemical calculation, as well as by comparison of their spectroscopic data with those reported. In the cytotoxic assay, showed inhibitory activity against human breast cancer MDA-MB-231 cell line with IC value of 7.68±1.74 μmol/L, and inhibited growth of human cervical cancer Hela cell line, melanoma A375 cell line and promyelocytic leukemia HL-60 cell line, with IC 12.00±2.08, 17.44±2.11, and 13.95±5.74 μmol/L, respectively.

Liposoluble constituents from Iodes cirrhosa and their neuroprotective and potassium channel-blocking activity / 中国中药杂志

<p><b>OBJECTIVE</b>To study the chemical constituents of Iodes cirrhosa and evaluate their bioactivity.</p><p><b>METHOD</b>The compounds were isolated and purified by various kinds of column chromatography methods and their structures were determined by spectroscopic data analysis. Neuroprotective assay against serum deprivation induced SH-SYSY-JNK3 cell apoptosis was evaluated by MTr method while potassium channel-blocking activity was assayed in both non-specific and specific K+ channel-regulator screening models.</p><p><b>RESULT</b>Twenty-one compounds were obtained from an EtOAc portion of an ethanolic extract of the root of I. cirrhosa. Their structures were elucidated as 1beta, 3beta-dihydroxyurs-9(11),12-diene(1), bauerenyl acetate(2),3beta-hydroxy-11-oxo-olean-12-enyl palmitate(3), 3beta-acetoxy-urs-12-ene-11-one(4), betulinic acid(5), stigmasta-5, 22-diene-3beta-ol(6), 7beta-hydroxystigmasterol(7), stigmasta-5, 22diene-3beta-ol3-O-beta-D-glucopyranoside(8),scopoletin(9),scopolin(10),clovamide(11),methyl 3,5-di-O-caffeoylquinate(12),3,5-dicaffeoylquinic acid(13),2,6-dimethoxy-1,4-benzoquinone(14), protocatechualdehyde(15), vanillin(16), protocatechuic acid(17), vanillic acid(18),caffeic acid(19),azelaic acid(20),and succinic acid(21). Compound 3,4,6,9,10,14,15,18 and 20 showed neuroprotective activities against serum deprivation induced SH-SYSY-JNK3 cell apoptosis at a concentration of 1.0 x 10(6) mol x L(1) with relative protection rates of 177%, 144%, 137%, 137%, 143%, 145%, 137%, 189%, 130%, respectivley. Compound 16 could increase DiBAC4(3) fluorescence response in both non-specific and specific K+ channel-regulator screening models at the concentration of 1.0 x 10(-5) mol x L(-1).</p><p><b>CONCLUSION</b>Compound 1 was a new compound and all compounds were isolated from this genus for the first time. Compounds 3,4,6,9,10,14,15,18 and 20 showed neuroprotective activities while 16 exhibited K+ channel-blocking activity.</p>

Constituents of Gymnadenia conopsea / 中国中药杂志

<p><b>OBJECTIVE</b>To investigate the chemical constituents of tuber of Gymnadenia conopsea.</p><p><b>METHOD</b>The constituents were isolated by using a combination of various chromatographic techniques including column chromatography over silica gel, Sephadex LH-20, and C-18, as well as reversed-phase HPLC. Structures of the isolates were identified by spectroscopic data analysis.</p><p><b>RESULT</b>Thirty-four compounds were isolated. Their structures were identified as six 2-isobutyltartrate benzyl ester glucosides: coelovirin A (1), coelovirin B (2), coelovirin E (3), coelovirin D (4), dactylorhin B (5) and loroglossin (6). Three 2-isobutylmalate benzyl ester glucosides: dactylorhin A (7), dactylorhin E (8) and militarine (9). Three lignans: arctigenin (10), lappaol A (11) and lappaol F (12). Six aromatic acid (alhyde or alcohol) derivatives: 4-beta-D-glucopyranosyloxyl-trans-phenylpropenoic acid (13), 4-beta-D-glucopyranosyloxyl-cis-phenylpropenoic acid (14), gastrodin (15), 4-beta-D-glucopyranosyloxylphenylaldehyde (16), 4-beta-D-glucopyranosyloxylbenzyl methyl ether (17), 4-beta-D-glucopyranosyloxyloxylbenzyl ethyl ether (18), and bis(4-hydroxybenzyl) ether mono 4-O-beta-D-glucopyranoside (19). Four cyclodipeptides: cyclo(L-Leu-L-Tyr) (20), cyclo(L-Leu-L-Pro) (21), cyclo(L-Val-L-Tyr) (22), and cyclo(L-Ala-D-Phe) (23). One N6-substituted andenosine: N6-(4-hydroxybenzyl)-adenine riboside (24). An aromatic amide: N-trans-feruloyltyramine (25). Nine aromatic acids (or aldehyde or alcohol): 3-hydroxybenzoic acid (26), 4-hydroxyisophthalic acid (27), 4-hydroxybenzyl alcohol (28), 4-hydroxybenzyl methyl ether (29), 4-hydroxybenzylaldehyde (30), 4-hydroxybenzoic acic (31), 4-hydroxy-3-methoxybenzoic acid (32), trans-p-hydroxyphenylpropenoic acid (33), and cis-p-hydroxyphenylpropenoic acid (34). At a concentration of 1.0 x 10(-6) mol x L(-1), compounds 10-12 showed antioxidative activity inhibiting Fe(+2) -cystine induced rat liver microsomal lipid peroxidation with inhibitory rates of 53%, 59%, and 52%, respectively(positive control VE with 35% inhibition).</p><p><b>CONCLUSION</b>These compounds were obtained from the genus Gymnadenia for the first time except for 5-7, 9, 15, 28-34. Compounds 10-12 possess antioxidant activity.</p>

Constituents from a water-soluble portion of ethanolic extract of Iodes cirrhosa / 中国中药杂志

<p><b>OBJECTIVE</b>To investigate chemical constituents of Iodes cirrhosa.</p><p><b>METHOD</b>Constituents were isolated by using a combination of various chromatographic techniques including column chromatography over silica gel, Sephadex LH-20, and C-18, as well as reversed-phase HPLC. Structures of the isolates were identified by spectroscopic and chemical methods.</p><p><b>RESULT</b>Twenty-four compounds were obtained from a H2O-soluble portion of an ethanolic extract of the root of lodes cirrhosa Turcz. Structures of the isolates were identified as (-)-(7R,8S,7'E) -4,7,9,9'-tetrahydroxy-3,3'-dimethoxy-8,4'-oxyneolign-7'-ene-9'-O-beta-D-glucopyra-noside (1), (-)-(7S,8S,7'E)-4,7,9,9'-tetrahydroxy-3,3'-dimethoxy-8,4'-oxyneolign-7'-ene-9'-O-beta-D-glucopyranoside(2), (+)-(7S,8S)-syringylglycerol 8-O-beta-D-glucopyranoside (3), (+)-(7S, 8S)-guaiacylglycerol 8-O-P-D-glucopyranoside (4), (-)-(7S, 8S)-4,7,9, 9'-tetrahydroxy-3,3'-dimethoxy-8,4'-oxyneolignan-7-O-beta-D-glucopyranoside (5),(-)-alaschanisoside A (6), (-)-(2R)-1-O-beta-D-glucopyranosyl-2-(2-methoxy-4-[1-(E)-propen-3-ol] phenoxyl propane-3-ol(7), (-)-(2R)-1-O-beta-D-glucopyranosyl-2-{2,6-dimethoxy-4-[1-(E)-propen-3-ol] phenoxyl} propane-3-ol(8), (-)-liriodendrin(9), (-)-(7S, 8R)-guaiacylglycerol 9-O-beta-D-glucopyranoside(10), (-)-(7R, 8R)-guaiacylglycerol 9-O-beta-D-glucopyranoside(11),(-)-(7R,8R)-syringylglycerol 9-O-beta-D-glucopyranoside(12), (-)-(7R,8R)-guaiacylglycerol 7-O-beta-D-glucopyranoside(13), (-)-11,13-dihydrodeacylcynaropicrin 3-O-beta-D-glucopyranoside(14), (-)-sweroside (15), (-)-2-hydroxy-5-(2-hydroxyethyl) phenyl beta-D-glucopyranoside(16), (-)-(1'R)-1'-(3-hydroxy-4-methoxyphenyl) ethane-1',2'-diol-3-O-beta-D-glucopyranoside(17), (-)-tachioside(18), (-)-3,5-dimethoxy-4-hydroxyphenyl beta-D-glucopyranoside(19), (-)-3-hydroxy-1-(4-hydroxy-3-methoxyphenyl)-1-propanone-3-O-beta-D-glucopy ranoside(20), (-)-2-methoxy4-(1-propionyl) phenyl beta-D-glucopyranoside(21), (-)-4-propionyl-3, 5-dimethoxyphenyl beta-D-glucopyranoside(22), erigeside C(23), and scopoletin beta-D-xylopyranosyl-(1-->6)-beta-D-glucopyranoside(24).</p><p><b>CONCLUSION</b>Compounds 1-24 were obtained from the genus for the first time.</p>