Occurrence of indole alkaloids among secondary metabolites of soil Aspergillus

The occurrence of indole alkaloids among secondary fungal metabolites was studied in species of the genus Aspergillus, isolated from soils that were sampled in various regions of Russia (a total of 102 isolates of the species A. niger, A. phoenicis, A. fumigatus, A. flavus, A. versicolor, A. ustus, A. clavatus, and A. ochraceus). Clavine alkaloids were represented by fumigaclavine, which was formed by A. fumigatus. alpha-Cyclopiazonic acid was formed by isolates of A. fumigatus, A. flavus, A. versicolor, A. phoenicis, and A. clavatus. The occurrence of indole-containing diketopiperazine alkaloids was documented for isolates of A. flavus, A. fumigatus, A. clavatus, and A. ochraceus. No indole-containing metabolites were found among the metabolites of A. ustus or A. niger.     

Microheterogeneity of molecular forms of arginase in mammalian tissues

Two isoforms of arginase, A1 and A2, were found in rat liver, submaxillary gland and kidney as well as beef kidney. In beef liver, however, A2 was the only detectable form. Two additional forms, A3 and A4, found only in rat kidney were probably artifactitious. A1 and A2 exhibited chromatographic and immunological microheterogeneity. While A1 in rat liver and submaxillary gland was excluded by DEAE-cellulose (pH 8.3) and retained on CM-cellulose (pH 7.5), that (A'1) in beef and rat kidneys was excluded by both ion-exchangers. A2 in all tissues was retained on DEAE-cellulose, but not on CM-cellulose. Both A1 and A2 in rat liver and beef kidney, A1 from rat submaxillary gland and A2 from beef liver were precipitated by antibodies to rat and beef liver arginases. None of the forms in rat kidney (A1, A2, A3 and A4) showed any cross-reactivity to either antibody. Rat submaxillary gland A2 was precipitated by anti-rat liver arginase, but activated by anti-beef liver arginase. While the major molecular forms were A1 in rat liver and submaxillary gland and A2 in beef liver and rat kidney, the two forms occurred in equal proportions in beef kidney. It appears that different isoforms might function as components of the urea cycle in the liver of different mammals and of the arginine catabolic pathway in different extrahepatic tissues.     

广义青篱竹属(Arundinaria)核糖体DNA ITS序列及亲缘关系研究

利用PCR扩增产物直接测序的方法分析广义青篱竹属(Arundinaria)中有关争议类群的代表种或模式种(毛竹为外类群)等18种竹种的核糖体DNA内转录间隔区(Internal Transcribed Spacers,ITS)序列。通过最简约性分析产生的ITS系统发育树表明,供试竹种形成一个自然的单系类群,这说明广义青篱竹属中这些不同的类群归属青篱竹属是合理的。17种竹种可聚为2大分支：其中斑苦竹(A,oleosa)、仙居苦竹(A．hsienchuensis)、茶秆竹(A．amabilis)、长叶苦竹(A．chino)、苦竹(A．amara)、宜兴苦竹(A．yixingensis)、菲白竹(A．fortunei)、翠竹(A．pygmaea)为一个分支;而大明竹(A．graminea)、巴山木竹(A．fargesii)、冷箭竹(A．faberi)、凤竹(A．hupehense)、鼓节矢竹(Pseudosasa japonica cv．Tsutsumiana)、矢竹(Pseudosasa japonica)、短穗竹(Brachystachyum densiflorum)、肿节竹(A．oedogonata)、少穗竹(A．sulcata)组合在另一分支。ITS系统发育树还表明,大明竹与巴山木竹、鼓节矢竹与矢竹、少穗竹与短穗竹和肿节竹关系极为密切,均得到较高的Bootstrap(分别为99％、100％和87％)的支持;茶秆竹与仙居苦竹关系非常密切,茶秆竹可归隶到青篱竹属中;翠竹和菲白竹关系密切,且与苦竹类竹种分为两个分支。     

The phylogenetic relationship of possible progenitors of the cultivated peanut

The cultivated peanut (Arachis hypogaea L.) is an allotetraploid composed of A and B genomes. The phylogenetic relationship among the cultivated peanut, wild diploid, and tetraploid species in the section Arachis was studied based on sequence comparison of stearoyl-ACP desaturase and oleoyl-PC desaturase. The topology of the trees for both fatty acid desaturases displayed two clusters; one cluster with A genome diploid species and the other with B genome diploid species. The two homeologous genes obtained for each of the two fatty acid desaturases from the tetraploid species A. hypogaea and A. monticola were separated into the A and B genome clusters, respectively. The gene phylogenetic trees showed that A. hypogaea is more closely related to the diploid species A. duranensis and A. ipaensis than to the wild tetraploid species A. monticola, suggesting that A. monticola is not a progenitor of the cultivated peanut. In addition, for the stearoyl-ACP desaturase, the A. duranensis sequence was identical with one of the sequences of A. hypogaea and the A. ipaensis sequence was identical with the other. These results support the hypothesis that A. duranensis and A. ipaensis are the most likely diploid progenitors of the cultivated tetraploid A. hypogaea.     

蜜蜂属六蜂种间MRJP2基因C-端重复序列的比较分析

构建了中华蜜蜂（Apis cerana cerana,中蜂）8日龄工蜂头部cDNA文库,获得了中蜂王浆主蛋白2（major royal jelly protein 2,MRJP2）的全长cDNA序列,该序列长1 605bp,包含一个编码468个氨基酸的开放阅读框（open reading frame,ORF）。在中蜂MRJP2的cDNA序列的C-端,首次发现存在串联重复片段长度多态性（variable numbers of tandem repeat,VNTR）。克隆并测定了蜜蜂属Apis内其他5个种的MRJP2基因的C-端重复序列,结果表明: 在蜜蜂属的其他5个种中,C-端重复片段的核心序列是以碱基高度突变方式而表现出个体之间的多态性,而重复片段长度基本一致。中蜂与西方蜜蜂A. mellifera,大蜜蜂A. dorsata与黑大蜜蜂A. laboriosa,以及小蜜蜂A. florea与黑小蜜蜂A. andreniformis分别形成3个进化枝。中蜂和西方蜜蜂与大蜜蜂和黑大蜜蜂之间的亲缘关系较近,而与小蜜蜂和黑小蜜蜂的亲缘关系较远。     

Classification of A1- and A24-supertype molecules by analysis of their MHC-peptide binding repertoires

At the functional level, the majority of human leukocyte antigen (HLA) class I MHC variants can be classified into about ten different major groups, or supertypes, characterized by overlapping peptide binding motifs and repertoires. Previous studies have detailed the peptide binding specificity of the HLA A2, A3, B7, and B44 supertypes, and predicted, on the basis of MHC pocket structures, known motifs, or the sequence of T cell epitopes, the existence of the HLA A1 and A24 supertypes. Direct experimental validation of the A1 and A24 supertypes, however, has been lacking. In the current study, the peptide-binding repertoires and main anchor specificities of several common HLA A molecules (A*0101, A*2301, A*2402, A*2601, A*2902, and A*3002) predicted to be members of the A1 or A24 supertypes were analyzed and defined using single amino acid substituted peptides and a large peptide library. Based on the present findings, the A1 supertype includes A*0101, A*2601, A*2902, and A*3002, whereas the A24 supertype includes A*2301 and A*2402. Interestingly, A*2902 is associated with a motif and peptide binding repertoire that overlaps significantly with those of all of the A1- and A24-supertype molecules studied, representing—to our knowledge—the first report of significant cross-reactivity among molecules belonging to different supertypes.     

Molecular phylogenetic perspective on evolution of lizards of the Anolis grahami series

We report the results of phylogenetic analyses of 1447 bases of mitochondrial DNA sequence for 21 populations representing seven species of the Anolis grahami series (A. conspersus, A. garmani, A. grahami, A. lineatopus, A. opalinus, A. reconditus, and A. valencienni), six of which occur on Jamaica. These data include 705 characters that are phylogenetically informative according to parsimony. A parsimony analysis of these data combined with previously published allozymic data yields a single most parsimonious tree with strong support for monophyly of the A. grahami series, the sister-group relationship between Anolis lineatopus and A. reconditus and a clade composed of Anolis garmani, A. grahami, and A. opalinus. Based on DNA data alone, A. conspersus is nested within A. grahami. Haplotypes sampled from geographic populations of A. grahami, A. lineatopus, and A. opalinus are highly divergent (approximately 12-15% sequence difference on average for each species) and show similar phylogeographic patterns, suggesting that each of these currently recognized species may be a complex of species. Anolis valencienni also shows high sequence divergence among haplotypes from different geographic populations (approximately 8% sequence difference) and may contain cryptic species. Divergence among haplotypes within A. garmani is substantially lower (approximately 3% sequence difference), and phylogeographic patterns are significantly different from those observed in A. grahami, A. lineatopus and A. opalinus.     

The phosphorylation of the primary gene products of alpha-crystallin

The alpha-crystallin primary gene product A2 and its post-translational modified counterpart A1 were isolated from calf lens cortex. The amino acid compositions determined from both chains were almost identical and in excellent agreement with that calculated from the reported sequence of A2. Chemical analysis of phosphate revealed 1 mol/mol of A1 and was negative in A2. Phosphoamino acid analysis demonstrated the presence of phosphoserine only in A1. Chymotryptic peptide maps of A2 and A1 resolved approximately 50 peptides and were strikingly similar. An apparent change in the relative mobility of one peptide was the only difference observed between A1 and A2. Phosphate analysis of this peptide obtained from A1 and A2 was positive only in the peptide from A1. Identical amino acid composition and the sequence Arg-Leu-Pro-Ser-Asn-Val-Asp-Gln-Ser-Ala-Leu was found for the peptide isolated from both chains, corresponding to residues 119 to 129 in the reported sequence of A2. These results indicate that the post-translational modification of A2 to A1 is the result of a phosphorylation reaction rather than a spontaneous nonenzymatic deamidation as previously suggested.     

Spectrum Analysis of Esterase Isozymes of culti-species and wild Species in Arachis

The electrophoresis analysis of isozymes of Arachis show a very close relationship among four types of cultispecies (A. hypogaea) and A. monticola, the tetraploid wild species is a related species. Among the five diploid wild species of Arachis Section, both A. cardenasii with A genome and A. batizocoi with B genome are found to be relatively nearer to cultis'pecies than A. correntina, A. stenosperma and A. villosa, while A. rigonii of Erectoides Section and A. pusilla of Triseminala Section are the distant species.     

Isolation of an activation intermediate and determination of the amino acid sequence of the activation segment of human pepsinogen A

Upon activation of human pepsinogen A at pH 2.0 in the presence of pepstatin, an intermediate form was generated together with pepsin A. This activation intermediate could be separated from pepsinogen A and pepsin A by DE-32 cellulose chromatography at pH 5.5. It had a molecular weight intermediate between those of pepsinogen A and pepsin A, and contained about half the number of basic amino acid residues in pepsinogen A. It had phenylalanine as the amino(N)-terminal amino acid, and was deduced to be generated by release of N-terminal 25 residue segment from pepsinogen A. Amino acid sequence determination of the N-terminal portions of pepsinogen A and the intermediate from enabled us to elucidate the entire acid sequence of the 47-residue activation peptide segment as follow: [Formula: see text]. On the other hand, upon activation of pepsinogen A at pH 2.0 in the absence of pepstatin, cleavage of the activation segment occurred at several additional bonds. In addition, upon activation both in the presence and in the absence of pepsitatin, an additional activation intermediate, designated pepsin A', was formed in minor quantities. This form was identical with pepsin A, except that it had an additional Pro-Thr-Leu sequence preceding the N-terminal valine of pepsin A.     

Application of epidermal characters to the taxonomy of European species of Antirrhinum (Schrophulariaceae)

Epidermal characters provide additional features in the assessment of taxonomic relationships among the European species of Antirrhinum. Much of this study confirms the classification derived by Webb but important differences have been observed, viz. A. mollissimum may be considered as identical to A. molle whilst A. boissieri, A. ambiguum and A. rupestre may be assigned as distinct species. Evidence from epidermal characters supports Rothmaler's view that A. majus spp. litigiosum is a subspecies of A. majus and should not be amalgamated with A. barrelieri as proposed by Webb. A. × huteri is proposed to be a hybrid between A. hispanicum and A. boissieri. Thus it is proposed that the section Antirrhinum comprises 20 species with A. majus divided into five subspecies.     

Occurrence of Indole Alkaloids among Secondary Metabolites of Soil Aspergillus Spp.

The occurrence of indole alkaloids among secondary fungal metabolites was studied in species of the genus Aspergillus, isolated from soils that were sampled in various regions of Russia (a total of 102 isolates of the species A. niger, A. phoenicis, A. fumigatus, A. flavus, A. versicolor, A. ustus, A. clavatus, and A. ochraceus). Clavine alkaloids were represented by fumigaclavine B, which was formed by A. fumigatus. -Cyclopiazonic acid was formed by isolates of A. fumigatus, A. flavus, A. versicolor, A. phoenicis, and A. clavatus. The occurrence of indole-containing diketopiperazine alkaloids was documented for isolates of A. flavus, A. fumigatus, A. clavatus, and A. ochraceus. No indole-containing metabolites were found among the metabolites of A. ustus or A. niger.     

Role of A1 adenosine receptors in regulation of vascular tone

The vascular response to adenosine and its analogs is mediated by four adenosine receptors (ARs), namely, A(1), A(2A), A(2B), and A(3). A(2A)ARs and/or A(2B)ARs are involved in adenosine-mediated vascular relaxation of coronary and aortic beds. However, the role of A(1)ARs in the regulation of vascular tone is less well substantiated. The aim of this study was to determine the role of A(1)ARs in adenosine-mediated regulation of vascular tone. A(1)AR-knockout [A(1)AR((-/-))] mice and available pharmacological tools were used to elucidate the function of A(1)ARs and the impact of these receptors on the regulation of vascular tone. Isolated aortic rings from A(1)AR((-/-)) and wild-type [A(1)AR((+/+))] mice were precontracted with phenylephrine, and concentration-response curves for adenosine and its analogs, 5'-N-ethyl-carboxamidoadenosine (NECA, nonselective), 2-chloro-N(6)-cyclopentyladenosine (CCPA, A(1)AR selective), 2-(2-carboxyethyl)phenethyl amino-5'-N-ethylcarboxamido-adenosine (CGS-21680, A(2A) selective), and 2-chloro-N(6)-3-iodobenzyladenosine-5'-N-methyluronamide (Cl-IBMECA, A(3) selective) were obtained to determine relaxation. Adenosine and NECA (0.1 microM) caused small contractions of 13.9 +/- 3.0 and 16.4 +/- 6.4%, respectively, and CCPA at 0.1 and 1.0 microM caused contractions of 30.8 +/- 4.3 and 28.1 +/- 3.9%, respectively, in A(1)AR((+/+)) rings. NECA- and CCPA-induced contractions were eliminated by 100 nM of 1,3-dipropyl-8-cyclopentylxanthine (DPCPX, selective A(1)AR antagonist). Adenosine, NECA, and CGS-21680 produced an increase in maximal relaxation in A(1)AR((-/-)) compared with A(1)AR((+/+)) rings, whereas Cl-IBMECA did not produce contraction in either A(1)AR((+/+)) or A(1)AR((-/-)) rings. CCPA-induced contraction at 1.0 microM was eliminated by the PLC inhibitor U-73122. These data suggest that activation of A(1)ARs causes contraction of vascular smooth muscle through PLC pathways and negatively modulates the vascular relaxation mediated by other adenosine receptor subtypes.     

Interaction of human pancreatic ribonuclease with human ribonuclease inhibitor. Generation of inhibitor-resistant cytotoxic variants

Mammalian ribonucleases interact very strongly with the intracellular ribonuclease inhibitor (RI). Eukaryotic cells exposed to mammalian ribonucleases are protected from their cytotoxic action by the intracellular inhibition of ribonucleases by RI. Human pancreatic ribonuclease (HPR) is structurally and functionally very similar to bovine RNase A and interacts with human RI with a high affinity. In the current study, we have investigated the involvement of Lys-7, Gln-11, Asn-71, Asn-88, Gly-89, Ser-90, and Glu-111 in HPR in its interaction with human ribonuclease inhibitor. These contact residues were mutated either individually or in combination to generate mutants K7A, Q11A, N71A, E111A, N88R, G89R, S90R, K7A/E111A, Q11A/E111A, N71A/E111A, K7A/N71A/E111A, Q11A/N71A/E111A, and K7A/Q11A/N71A/E111A. Out of these, eight mutants, K7A, Q11A, N71A, S90R, E111A, Q11A/E111A, N71A/E111A, and K7A/N71A/E111A, showed an ability to evade RI more than the wild type HPR, with the triple mutant K7A/N71A/E111A having the maximum RI resistance. As a result, these variants exhibited higher cytotoxic activity than wild type HPR. The mutation of Gly-89 in HPR produced no change in the sensitivity of HPR for RI, whereas it has been reported that mutating the equivalent residue Gly-88 in RNase A yielded a variant with increased RI resistance and cytotoxicity. Hence, despite its considerable homology with RNase A, HPR shows differences in its interaction with RI. We demonstrate that interaction between human pancreatic ribonuclease and RI can be disrupted by mutating residues that are involved in HPR-RI binding. The inhibitor-resistant cytotoxic HPR mutants should be useful in developing therapeutic molecules.     

中药砂仁类资源植物药理活性的比较

本文对6种砂仁类中药水煎液及挥发油进行了抑菌作用和对小鼠小肠运动影响的比较研究。结果表明春砂仁、壳砂仁和建砂仁的水煎液对革兰氏阳性菌（G+）有抑制作用;川砂仁挥发油、建砂仁水煎液对革兰氏阴性菌（G-）有抑制作用;红壳砂仁挥发油及水煎液对革兰氏阳性菌（G+）与革兰氏阴性菌（G-）均有抑制作用,而绿壳砂均无抑制作用。砂仁类的水煎液对促进肠管运动有明显作用,而挥发油即使在稀释100倍的情况下对肠管运动仍起抑制作用。     

17种桤木属植物的亲缘关系研究及模糊种鉴定

利用AFLP分子标记结合形态学指标,采用UPGMA法进行聚类分析,对桤木属17个种57份材料进行了亲缘关系研究及一个模糊种鉴定。结果表明：7对引物扩增出369条带,其中346个多态位点,多态位点百分率为93.77%;根据AFLP标记位点聚类分析,在相似系数为0.782时,17种桤木属植物可分为4类,第一类为日本桤木(Alnus japonica);第二类为绿桤木(A.viridis)、意大利桤木(A.cordata)、欧洲桤木(A.glutinosa)、模糊种、四川桤木(A.cremastogyne)、江南桤木(A.trabeculosa)、斑点桤木(A.incana ssp.rugosa)、东北亚灰桤木(A.hirsuta)、台湾桤木(A.formosana)、日本特有桤木(A.firma)和裂叶桤木(A.sinuata);第三类为灰桤木(A.incana)、红桤木(A.rubra)及薄叶桤木(A.tenifolia);第四类喜马拉雅灰桤(A.nitida)和尼泊尔桤木(A.nepalensis)。根据形态学聚类分析,在距离为1.4时可分为三类,意大利桤木(A.cordata)单独为一类;日本桤木(A.japonica)、台湾桤木(A.formosana)、喜马拉雅灰桤木(A.nitida)、江南桤木(A.trabeculosa)和东北亚灰桤木(A.hirsuta);第三类包括模糊种、灰桤木(A.incana)、斑点桤木(A.incana ssp.rugosa)、裂叶桤木(A.sinuata)、红桤木(A.rubra)、欧洲桤木(A.glutinosa)、绿桤木(A.viridis)、四川桤木(A.cremastogyne)、薄叶桤木(A.tenuifolia)和尼泊尔桤木(A.nepalensis)。经形态特征和AFLP分析鉴定模糊种为欧洲桤木。形态学聚类与AFLP聚类结果基本一致,但仍存在一定的差异,说明桤木属植物遗传背景丰富,种的分子分类地位和形态学分类地位具有一定的差异。     

Three Novel Chemical Compounds of Annonaceous Acetogenins from the Seeds of Annona squamosa

Seven compounds (A1--A7) were isolated from the seeds of Annona squamosa L. Three of them, A2, A3, and A5, are new compounds of annonaeeous aeetogenins, and they were name neo-desacetyluvaricin (A2), neo-annonin B (A3) and neo-reticulatacin A (A5), respectively.