A pistil-specific thaumatin/PR5-like protein gene of Japanese pear (Pyrus serotina): sequence and promoter activity of the 5′ region in transgenic tobacco

The genomic clone encoding the pistil-specific thaumatin/PR5-like protein (PsTL1) was isolated from Japanese pear (Pyrus serotina). Sequence analysis showed that the genomic clone contained the 5-flanking sequence of 2.4 kb, the 3-flanking sequence of 648 bp and the coding region interrupted by a intron of 351 bp. A sequence motif conserved in some pistil self-incompatibility gene promoters of solanaceous and brassicaceous species was located in the 5-flanking region of the PsTL1 gene. The 2.4 kb 5-flanking region was fused to the GUS coding sequence and transferred to tobacco. Transgenic tobacco showed GUS activity in pistil and, at low level, in anther, but not in other floral organs and leaf. Histochemical analysis localized GUS activity to stigma, transmitting tissue, anther and pollen of transgenic tobacco.     

Analysis of an ABA-responsive rice gene promoter in transgenic tobacco

We have analyzed in transgenic tobacco the expression of a chimeric gene containing 5 sequences of the rice rab-16B gene fused to the -glucuronidase (GUS) reporter gene. This construct, a translational fusion (–482 to +184) including 14 amino acids of the RAB-16B protein, is expressed only in zygotic and pollen-derived embryos. In zygotic embryos, GUS activity begins to accumulate 10 days after flowering (daf), and increases until seed maturation at 25 daf. Immunological measurements of endogenous abscisic acid (ABA) accumulation in these seeds showed a close parallel between hormone levels and GUS activity. However, GUS activity could not be reproducibly induced by treatment of immature embryos with ABA (10 M). Neither GUS activity nor GUS mRNA could be detected in leaves of transgenic tobacco even after ABA treatment. In contrast, GUS activity could be induced to high levels in pollen-derived embryos by treatment with ABA. Our results show that 482 bp of 5 sequences of the rice rab-16B promoter can confer in transgenic tobacco developmentally regulated expression in embryos but not ABA-responsive expression in vegetative tissues.     

Polymerization of nucleotide analogues I: Reaction of nucleoside 5′-phosphorimidazolides with 2′-amino-2′-deoxyuridine

Summary 2-Amino-2-deoxyuridine reacts efficiently with nucleoside 5-phosphorimidazolides in aqueous solution. The dinucleoside monophosphate analogues were obtained in yields exceeding 80% under conditions in which little reaction occurs with the natural nucleosides.In a similar way, the 5-phosphorimidazolide of 2-amino-2-deoxyuridine undergoes self-condensation in aqueous solution to give a complex mixture of oligomers.The phosphoramidate bond in the dinucleoside monophosphate analogues is stable for several days at room temperature and pH 7. The mechanisms of their hydrolysis under acidic and alkaline conditions are described.Abbreviations A adenosine - C cytidine - G guanosine - U uridine - T thymidine - U_{N 3} 2-azido-2-deoxyuridine - U_{NH 2} 2-amino-2-deoxyuridine - ImpA adenosine 5-phosphorimidazolide - ImpU uridine 5-phosphorimidazolide - ImpU_{N 3} 2-azido-2-deoxyuridine 5-phosphorimidazolide - ImpU_{NH 2} 2-amino-2-deoxyuridine 5-phosphorimidazolide - pA adenosine 5-phosphate - pU uridine 5-phosphate - pU_{N 3} 2-azido-2-deoxyuridine 5-phosphate - pU_{NH 2} 2-amino-2-deoxyuridine 5-phosphate - UpA uridylyl-[35]-adenosine - UpU uridylyl-[35]-uridine - U_NpA adenylyl-[52]-2-amino-2-deoxy-uridine - U_NpU uridylyl-[52]-2-amino-2-deoxyuridine (pU_N)_n n=2,3,4 [25]-linked oligomers of pU_{NH 2} poly(A) polyadenylic acid - Im imidazole - MeIm l-methylimidazole     

Erratum: Cloning and sequencing of the phycocyanin gene from Spirulina maxima and its evolutionary analysis

The genes were cloned for the two apoprotein subunits, and ,of phycocyanin from the cyanobacterium Spirulina maxima = Arthrospiramaxima) strain F3. The - and -subunit gene-coding regionscontain 489 bp and 519 bp, respectively. The -subunit gene is upstreamfrom the -subunit gene, with a 111-bp segment separating them.Similarities between the -subunits of S. maxima and nine othercyanobacteria were between 58% and 99%, as were those between the -subunits. The maximum similarity between the - and -subunits from S. maxima was 27%.     

Analysis of kafirin promoter activity in transgenic tobacco seeds

Sequences corresponding to 855 bp of 5 promoter region and the transit peptide from GK.1, a genomic clone encoding a 22 kDa -kafirin seed protein from sorghum, were translationally fused to a cloned -glucuronidase (GUS) coding sequence from uidA and transferred to tobacco via Agrobacterium tumefaciens-mediated transformation. No GUS expression was detectable at any stage of growth in stems or leaves of these plants. However, GUS expression was detected in both embryo and endosperm tissues of resulting tobacco seeds 10–15 days after flowering. Dissected tissues indicate endosperm expression was localized within the bulk endosperm and not within the parenchyma cell layer underlying the integument. These studies also demonstrate that within dissected tobacco embryos, expression from the kafirin promoter was restricted to the mesocotyl region.     

The influence of increasing chlorine content on the accumulation and metabolism of polychlorinated biphenyls (PCBs) by Paul's Scarlet Rose cells

Four radiolabled congeners of biphenyls with increasing chlorine content (biphenyl; 1-monochlorobiphenyl; 2,2,4,4-tetrachlorobiphenyl; and 2,2,4,4,5,5-hexachlorobiphenyl) were provided to suspension cultures of rose (Rosa sp. cv. Paul's Scarlet) for 4 days. Both the kinetics of ¹⁴C exchange between the cells and medium, and the metabolism of the parent compounds depended on the chlorine content of the congeners. Analysis of both the cells and their medium showed that of the recovered radioactivity 88%, 86%, and 3% of the biphenyl, 1-PCB, and 2,2,4,4-PCB were metabolized respectively to polar and insoluble residue products. The 2,2,4,4,5,5-PCB did not appear to be metabolized.     

Template-directed reactions of aminonucleosides

Summary We have studied the reactions between adenosine 5-phosphorimidazolide and 9-(2-amino-2-deoxyxylofuranosyl) adenine (I) or 3-methylamino-3-deoxyadenosine (II), both with and without a poly (U) template. We find that both amino compounds react much more rapidly than does adenosine, in the absence of a template. The rate of reaction is greatly enhanced by a poly (U) template in the case of I, but the enhancement is slight in the case of II.Abbreviations A adenosine - xylo A_NH2 9-(2-amino-2-deoxy--D-xylofuranosyl) adenine - A_NHMe 3-methylamino-3-deoxyadenosine - ImpA adenosine 5-phosphorimidazolide - A³ pA adenylyl-[35]-adenosine - A² pA adenylyl-[25]-adenosine - U_NPA adenylyl-[52]-2-amino-2-deoxyuridine - xylo A_NPA 9-[adenylyl-(52)-2-amino-2-deoxy--D-xylofuranosyl]adenine - A_(NMe)pA adenylyl-[53]-3-methylamino-3-deoxyadenosine - pA adenosine 5phosphate - AppA P₁, P₂-diadenosine 5pyrophosphate - (pA)_n n = 2, 3 [2-5]-linked oligomers of pA - A² pA² pA [2-5]-linked trinucleoside diphosphate of A - poly (U) polyuridylic acid     

Stem distribution and clonal structure of Chamaecyparis pisifera growing in an old-growth beech-conifer forest

To elucidate sapling patch formation and the mode of regeneration occurring in Chamaecyparis pisifera, we investigated stem distribution and clonal structure of this species in an old-growth beech-conifer forest in central Japan. The study was carried out in a 1-ha plot using small and large sapling (d.b.h.<5cm, 0.5mheight<2 m and d.b.h.<5cm, height2m, respectively) and adult (d.b.h.5cm) stems of Chamaecyparis pisifera. The numbers of small and large sapling stems were 677 and 149 in the plot, respectively, and they were strongly aggregated. Adult stems occurred at much lower density (90 stems in the plot) and were weakly clustered. Fifty multilocus genotypes at nine allozyme loci were detected among sampled stems. Small and large sapling stems with identical genotypes showed aggregated distribution, while some neighboring adult stems had the same genotypes. Spatial autocorrelation of alleles in small and large sapling stems revealed a strongly positive association among stems within a distance of 10m; but a negative association as distance increased. In adult stems, a strongly positive value was found only in the shortest distance class. These results indicate that clonal growth by layering occurred at the sapling stage and contributed to patch formation. Our results also suggest that the clonal growth by layering is ecologically significant throughout the life history of Chamaecyparis pisifera, particularly as an important strategy for the sapling establishment in the early stage of regeneration process.     

β-Ether cleavage of the lignin model compound 4-ethoxy-3-methoxyphenylglycerol-β-guaiacyl ether and derivatives by Phanerochaete chrysosporium

The white rot basidiomycete Phanerochaete chrysosporium metabolized 4-ethoxy-3-methoxyphenyl-glycerol--guaiacyl ether (V) in low nitrogen, stationary cultures under which conditions the ligninolytic enzyme system is expressed. 4-Ethoxy-3-methoxyphenylglycerol XIII, guaicol and 4-ethoxy-3-methoxybenzyl alcohol (II) were isolated as metabolic products. Exogenously added XIII was rapidly converted to 4-ethoxy-3-methoxybenzyl alcohol indicating that it is an intermediate in the metabolism of V. P. chrysosporium also metabolized 1-(4-ethoxy-3-methoxyphenyl)-2-(2-methoxyphenoxy)-3-hydroxypropane VI. The degradation pathway for this dimer also included initial -ether cleavage and -hydroxylation of the diol product 1-(4-ethoxy-3-methoxyphenyl) 2,3 dihydroxypropane (XI) to yield the triol XIII which was cleaved at the , bond to yield 4-ethoxy-3-methoxybenzyl alcohol. Finally P. chrysosporium also cleaved the dimer 1-(4-ethoxy-3-methoxyphenyl)-2-(2-methoxyphenoxy)-1-hydroxypropane (VIII) at the -ether linkage yielding 1-(4-ethoxy-3-methoxyphenyl) 1,2 dihydroxypropane (IX) which was subsequently cleaved at the , bond to yield II. All of the results indicate that oxidative -ether cleavage is an important initial reaction in the metabolism of -aryl ether lignin substructure dimeric compounds. Metabolities were identified after comparison with chemically synthesized standards by gas liquid chromatography-mass spectrometry.Abbreviations GLC Gas liquid chromatography - TMSi trimethylsilyl - TLC thin layer chromatography     

Chromosomal location and expression of the single-copy gene encoding high-mobility-group protein HMG-I/Y in Arabidopsis thaliana

A cDNA encoding the HMG-I/Y protein from Arabidopsis thaliana has been isolated and characterised by nucleotide sequencing. The 903 bp cDNA contains a 612 bp open reading frame encoding a protein of 204 amino acid residues showing homology to HMG-I/Y proteins from other plant species. The protein contains four copies of the AT-hook motif which is involved in binding A/T-rich DNA. Southern blotting showed that the HMG-I/Y gene was present in a single copy in the Arabidopsis genome. The gene was localised to the top of chromosome 1 by RFLP analysis of F₈ recombinant inbred lines. Northern blotting showed that the gene was expressed in all organs examined, with the highest expression in flowers and developing siliques.     

Adenosine-5′-phosphosulfate (APS) as sulfate donor for assimilatory sulfate reduction in Rhodospirillum rubrum

Crude extracts of Rhodospirillum rubrum catalyzed the formation of acid-volatile radioactivity from (³⁵S) sulfate, (³⁵S) adenosine-5-phosphosulfate, and (³⁵S) 3-phosphoadenosine-5-phosphosulfate. An enzyme fraction similar to APS-sulfotransferases from plant sources was purified 228-fold from Rhodospirillum rubrum. It is suggested here that this enzyme is specific for adenosine-5-phosphosulfate, because the purified enzyme fraction metabolized adenosine-5-phosphosulfate, however, only at a rate of 1/10 of that with adenosine-5-phosphosulfate. Further, the reaction with 3-phosphoadenosine-5-phosphosulfate was inhibited with 3-phosphoadenosine-5-phosphate whereas this nucleotide had no effect on the reaction with adenosine-5-phosphosulfate. For this activity with adenosine-5-phosphosulfate the name APS-sulfotransferase is suggested. This APS-sulfotransferase needs thiols for activity; good rates were obtained with either dithioerythritol or reduced glutathione; other thiols like cysteine, 2-3-dimercaptopropanol or mercaptoethanol are less effective. The electron donor methylviologen did not catalyze this reaction. The pH-optimum was about 9.0; the apparent K _m for adenosine-5-phosphosulfate was determined to be 0.05 mM with this so far purified enzyme fraction. Enzyme activity was increased with K₂SO₄ and Na₂SO₄ and was inhibited by 5-AMP. These properties are similar to assimilatory APS-sulfotransferases from spinach and Chlorella.Abbreviations APS adenosine-5-phosphosulfate - PAPS 3-phosphoadenosine-5-phosphosulfate - 5-AMP adenosine-5-monophosphate - 3-AMP adenosine-3-monophosphate - 3-5-ADP 3-phosphoadenosine-5-phosphate (PAP) - DTE dithiorythritol - GSH reduced glutathione - BAL 2-3-dimercaptopropanol     

Translation efficiency mediated by the 5′ untranslated region greatly affects protein production in <Emphasis Type="Italic">Aspergillus oryzae</Emphasis>

We demonstrate that the 5 untranslated region (5UTR) plays an important role in determining translation efficiency in Aspergillus oryzae, using a model -glucuronidase (GUS) expression system. Alterations in the 5UTR resulted in an increase in GUS activity of up to eight-fold, without affecting mRNA levels. Moreover, using the most effective 5UTR construct, we could achieve remarkable intracellular overproduction of GUS protein; and the GUS level reached more than 50% of the total soluble protein. This is the first experimental evidence indicating the feasibility of improving recombinant protein yield by promoting translation initiation in filamentous fungi.     

α-Isopropylmalate synthase from Alcaligenes eutrophus H 16

The purified isopropylmalate synthase of Alcaligenes eutrophus H 16 reacted with the following -keto acids and acyl-coenzyme A derivatives (in the sequence of decreasing affinities): -ketoisovalerate, -keto-n-valerate, -ketobutyrate and pyruvate; acetyl-CoA, propionyl-CoA, butyryl-CoA. malonyl-CoA, valeryl-CoA, and crotonyl-CoA. -Ketoisocaproate, however, is a strong inhibitor of the enzyme. All reactions catalyzed by isopropylmalate synthase were inhibited to the same extent by the endproduct l-leucine. the substrate saturation curves of -ketoisovalerate or other -keto acids and of acetyl-coenzyme A or other acyl-CoA derivatives had intermediary plateau regions; the Hill coefficient alternated between n _H -values higher and lower than 1.0, indicating changes from positive to negative and from negative to positive cooperativity for the substrates. The products, isopropylmalate and free coenzyme A, showed competitive inhibition patterns against both substrates (-ketoisovalerate and acetyl-CoA). Free coenzyme A (1 M) inactivated the enzyme irreversibly. The 3-phosphate of coenzyme A and the free carboxyl group of -ketoisovalerate were involved in optimal binding of these substrates, but 3-dephospho-acetyl-coenzyme A and the methylester of -ketoisovalerate were also converted by this enzyme. A CH₃–CH₂-grouping of the -keto acids seemed to be necessary for binding this substrate.Abbreviations Used CoA Coenzyme A - Tris Tris(hydroxymethyl)aminomethane hydrochloride - DTNB 5,5-dithiobis-(2-nitrobenzoic acid) - IPM -Isopropylmalate - KIV -Ketoisovalerate Prepared from doctoral thesis of the University of Göttingen 1973     

Poly(U)-directed peptide-bond formation from the 2′(3′)-glycyl esters of adenosine derivatives

Summary The self-condensation of 2(3)-O-glycyl esters of adenosine, adenosine-5-(O-methylphosphate) and P₁, P₂-diadenosine-5-pyrophosphate in 6.2 mM solutions at pH 8.0 and -5°C in the presence of 12.5 mM poly(U) yields approximately 3 times as much diketopiperazine as reactions without poly(U). As the concentration of 2(3)-O-(glycyl)-P₁, P₂-diadenosine-5-pyrophosphate is decreased from 6.2 mM to 1.5 mM the yield of diketopiperazine in the presence of poly(U) decreases slightly from 6.6% to 5.2%, whereas, in the absence of poly(U) the yield of diketopiperazine decreases substantially from 2.4% to 0.75%. The enhanced yield of diketopiperazine that is attributed to the template action of poly(U) is temperature dependent and is observed only at temperatures below 10°C (5°C to -5°C) for 6.2 mM 2(3)-O-(glycyl)-adenosine-5-(O-methylphosphate) and below 23°C (15°C to -5°C) for 6.2 mM 2(3)-O-(glycyl)-P₁, P₂-diadenosine-5-pyrophosphate. The absence of a template effect at high temperatures is attributed to the melting of the organized helices. The hydrolysis half-lives at pH 8.0 and -5°C of 2(3)-O-(glycyl)-adenosine, 2(3)-O-(glycyl)-adenosine-5-(O-methylphosphate), 2(3)-O-(glycyl)-P₁, P₂-diadenosine-5-pyrophosphate, and 5-O-(glycyl)-adenosine in the presence of poly(U) are substantially larger than their half-lives in the absence of poly(U). The condensation of 2(3)-O-(glycyl)-adenosine yields 5% of 5-O-(glycyl)-adenosine in the presence of poly(U) compared to 0.7% in the absence of poly(U).Abbreviations DKP diketopiperazine - (gly)₂ glycylglycine - (gly)₃ glycylglycylglycine - AppA-gly 2(3)-O-(glycyl)-P₁, P₂-diadenosine-5-pyrophosphate - MepA-gly 2(3)-O-(glycyl)-adenosine-5-(O-methylphosphate) - Ado-2(3)-gly 2(3)-O-(glycyl)-adenosine - Ado-5-gly 5-O-(glycyl)-adenosine - Boc-gly N-tert-butyloxycarbonylglycine - AppA P₁, P₂-diadenosine-5-pyrophosphate - MepA adenosine-5-(O-methylphosphate) - AppA-Boc-gly 2(3)-O-(Boc-glycyl)-P₁, P₂-diadenosine-5-pyrophosphate - Ado-5-Boc-gly 5-O-(Boc-glycyl)-adenosine - Ado-2(3)-Boc-gly 2(3)-O-(Boc-glycyl)-adenosine     

The formation of peptides from the 2′(3′)-glycyl ester of a nucleotide

Summary We have synthesized 2(3)-O-(glycyl)-adenosine-5-(O-methylphos-phate), an analogue of the 3-terminus of aminoacylated tRNA. A 0.4M solution of this compound maintained at pH 8.2, yields 5.5% of diglycine and 11.5% of diketopiperazine, in addition to the hydrolysis products glycine and adenosine-5-(O-methylphosphate). Under the same conditions, glycine ethyl ester reacts much more slowly, but ultimately gives similar yields of diglycine and diketopiperazine.The aminolysis of 2(3)-O-(glycyl)-adenosine-5-(O-methylphosphate) by free glycine is relatively inefficient, but serine reacts 20 times more rapidly and yields up to 50% of N-glycylserine. The prebiotic significance of these reactions is discussed.Abbreviations MepA adenosine-5-(O-methylphosphate) - MepA-gly 2(3)-O-(glycyl)-adenosine-5-(O-methylphosphate) - MepA-bis-gly 2,3-O-(bis-glycyl)-adenosine-5-(O-methylphosphate) - DKP diketopiperazine - gly Et glycine ethyl ester - gly-ser N-glycylserine - O-gly-ser O-glycylserine - O-(gly)-gly-ser O-(glycyl)-glycylserine - Boc-gly N-tert-butyloxycarbonylglycine - MepA-Boc-gly 2(3)-O-(Boc-glycyl)-adenosine-5-(O-methylphosphate) - MepA-bis-Boc-gly 2,3-O-(bis-Boc-glycyl)-adenosine-5(O-methylphosphate) - (gly)₂ diglycine - (gly)₃ triglycine     

The catalysis of nucleotide polymerization by compounds of divalent lead

Summary Soluble lead salts and a number of lead-containing minerals catalyze the formation of oligonucleotides from nucleoside 5-phosphorimidazolides. The effectiveness of lead compounds correlates strongly with their solubility. Under optimal conditions we were able to obtain 18% of pentamer and higher oligomers from ImpA. Reactions involving ImpU gave smaller yields.Abbreviations A adenosine - U uridine - Im imidazole - MeIm 1-methyl-imidazole - EDTA ethylenediaminetetraacetic acid - pA adenosine 5-phosphate - pU uridine 5-phosphate - Ap adenosine cyclic 2:3-phosphate - ATP adenosine 5-triphosphate - AppA P₁,P₂-diadenosine 5-diphosphate - pNp (N = A,U) nucleotide 2(3), 5-diphosphate - ImpA adenosine 5-phosphoreimidazolide - ImpU uridine 5-phosphorimidazolide - A ²pA adenylyl-[25]-adenosine - A ³pA adenylyl-[35]-adenosine - pA ²pA 5-phospho-adenylyl-[25]-adenosine - pA ³pA 5-phospho-adenylyl-[35]-adenosine - pUpU 5-phospho-uridylyl-uridine - pApU 5-phospho-adenylyl-uridine - pUpA 5-phospho-uridylyladenine - (pA)n (n, 2,3,4,) oligoadenylates with 5 terminal phosphate - ImpApA 5-phosphorimidazolide of adenylyl adenosine - (pA) ₅₊ pentamer and higher oligoadenylates with 5 terminal phosphate - (Ap)nA (n = 2,3,4) oligoadenylates without terminal phosphates In the following we do not specify the nature of the internucleotide linkageIn the following we do not specify the nature of the internucleotide linkage     

Physical properties and metabolite regulation of ribulose bisphosphate carboxylase from Thiobacillus A2

Purified ribulose-bisphosphate carboxylase (EC 4.1.1.39) was strongly and equally inhibited either by ADP or GDP and to a lesser extent by IDP. AMP or ATP exerted little effect on activity. Inhibition by the nucleotide diphosphates was competitive with respect to RuBP and non-competitive with respect to CO₂ and Mg²⁺, respectively. Treatment of the enzyme with urea or guanidine-HCl resulted in rapid loss of activity that was not restored by dialysis even in the presence of Mg²⁺ and cysteine. Sodium dodecyl sulfate electrophoresis of 8.0 M urea treated enzyme revealed the presence of a fast-moving (small) sub-unit with molecular weight 14150 and a slower moving (large) sub-unit with molecular weight 68000. Examination of native enzyme by sodium dodecyl sulfate electrophoresis gave sub-units of 13700 and 55500 respectively. The amino acid content standardized to phenylalanine was essentially similar to that from other sources. Arrhenius plots showed a break at 29°C with an E _a of 12.34 kcal per mole for the steeper part of the curve and a H of 11.43 kcal per mole while for the less steep region, the E _a was 1.04 kcal per mole and the H 1.92 kcal per mole.Abbreviations ADP adenosine-5-diphosphate - AMP adenosine-5-monophosphate - ATP adenosine-5-triphosphate - CDP cytidine-5-diphosphate - CMP cytidine-5-monophosphate - CTP cytidine-5-triphosphate - FDP fructose-1,6-diphosphate - F6P fructose-6-phosphate - GDP guanosine-5-diphosphate - GMP guanosine-5-monophosphate - G6P glucose-6-phosphate - GTP guanosine-5-triphosphate - IDP inosine-5-diphosphate - IMP inosine-5-monophosphate - PEP phosphoenolpyruvate - 6PG 6-phosphogluconate - R1P ribose-1-phosphate - R5P ribose-5-phosphate - RuBP ribulose-1,5-bisphosphate - SDS sodium dodecyl sulfate - TDP thymidine-5-diphosphate - TMP thymidine-5-monophosphate - TTP thymidine-5-triphosphate - UDP uridine-5-diphosphate - UMP uridine-5-monophosphate - UTP uridine-5-triphosphate     

Synthesis of oligoguanylates on oligocytidylate templates

Summary Short oligocytidylates can act as templates for the self-condensation of guanosine 5-phosphorimidazolide. In the absence of a catalytic metal ion or in the presence of Pb²⁺ a noticeable template effect is already observed with the dimer and the yield of long oligomers reaches a plateau with a hexamer template. Short templates give oligomers longers than the template length. The products are predominantly 2-5 linked for the Pb²⁺-catalyzed reaction while mixed linkages are observed in the uncatalyzed reaction.In the presence of Zn²⁺, a template effect is first observed with the pentamer and is maximal by the heptamer. The products are predominantly 3-5 linked. Oligomers shorter than or as long as the template are obtained in substantial yield, and longer products in much lower yields.Abbreviations G Guanosine - Gp guanosine 2(3)-phosphate - pG guanosine 5-phosphate - Gp! guanosine cyclic 2,3-phosphate - ImpG guanosine 5-phosphorimidazolide - ImpG^* [8-¹⁴C]-guanosine 5-phosphorimidazolide - pGp 5-phosphoguanosine 2(3)-phosphate - G²pG guanylyl-[2-5]-guanosine - G³pG guanylyl-[3-5]-guanosine - ImpGpG 5-phosphorimidazolide of GpG - (pG)_n (n = 2,3) oligomers of pG - GppG P₁, P₂-diguanosine 5-diphosphate - GppGpG 5-[guanosine 5-pyrophosphate] of GpG - NH₂pG guanosine 5-phosphoramidate - (pG)₄₊ tetramer and higher oligoguanylates with 5 terminal phosphate - oligo(G) oligoguanylate - Cp cytidine 2(3)-phosphate - Cp! cytidine cyclic 2,3-phosphate - (Cp)_n–1 Cp! (n= 2,3,4) oligocytidylates terminated by 5-OH groups and 2,3-cyclic phosphates - oligo(C) oligocytidylate - poly(C) polycytidylic acid - poly(U) polyuridylic acid - poly(C,G) random copolymer of C and G - BAP bacterial alkaline phosphatase (E. coli) - EDTA ethylenediaminetetraacetic acid - R_f chromatographic mobility