Morpho-colorimetric characterization by image analysis to identify diaspores of wild plant species

Digital images of ex situ germplasm stored in the Sardinian Germplasm Bank (BG-SAR) were used for the application of image analysis techniques at the Stazione Sperimentale di Granicoltura per la Sicilia. The analysed accessions refer to 148 taxonomic units belonging to 102 genera and 47 families, typical of the Sardinian flora, and of the Mediterranean basin in general.The images of diaspores were acquired by a flatbed scanner and elaborated with a macro specially developed for the morphometric and colorimetric measurements. This method allowed carrying out a database for the characterization of autochthonous germplasm in entry to the bank and the realization of statistic classifiers for the discrimination of genera and species within the following families: Apiaceae, Boraginaceae, Caryophyllaceae, Cistaceae, Fabaceae and Scrophulariaceae. Such classifiers, based on the linear discriminant analysis (LDA) technique and checked by cross-validation, showed a performance included between 74.3% and 96.4%.In addition, for the genus Astragalus, it was possible to elaborate a classifier able to identify very similar taxa of a species complex, obtaining a performance between 83.7% and 100%. Such analysis proved the validity of the methodology also from the taxonomic point of view.Suggestions for subsequent methodological progress, which could offer applications in other research issues, such as ecological analysis, soil seed bank and archaeological botany are proposed.     

大豆下胚轴可溶性蛋白中钙激活的蛋白激酶

大豆（Ｇｌｙｃｉｎｅ ｍ ａｘ Ｌ．） 下胚轴可溶性蛋白提取液进行自磷酸化，以ＳＤＳ－ＰＡＧＥ电泳分析其标记产物时发现，当有较高浓度的Ｃａ２＋ 存在于反应液中时，有一条１８ ｋＤ蛋白带被高强度标记，同时也可观察到另一条标记强度不高的６７ ｋＤ蛋白带． 当反应时间延长到１５ 或３０ｍ ｉｎ 时，它们的标记强度都逐渐减弱，最终从放射自显影底片上消失；在反应液中加入钙螯合剂ＥＧＴＡ 时，则只有６７ ｋＤ 被高强度标记；在磷酸化反应过程中加入非标记ＡＴＰ，蛋白中的３２Ｐ逐渐被非标记磷取代，表明反应体系处于磷酸化－脱磷酸化的平衡过程中，并有结果显示这一过程是钙依赖性的． 组蛋白Ｈ１ 可以使反应进程加快，表明提取液中的蛋白激酶可以利用它作为底物． 综合结果表明，１８ ｋＤ和６７ ｋＤ蛋白可能是具有自磷酸化能力且对Ｃａ２＋ 敏感的蛋白激酶，它们对Ｃａ２＋ 的不同反应，使得钙信号的传递更具可控性     

R-prime plasmids from Bradyrhizobium japonicum and Rhizobium fredii

The formation of R-prime plasmids was selected in crosses involving soybean microsymbionts with genomic Tn5 insertions and carrying plasmid pJB3JI (with one IS2) copy as donors and Escherichia coli HB101 as recipient. Whereas the parent plasmid was 60 kb, recombinant plasmids between 76 kb and 121 kb were obtained. Restriction and Southern analyses confirmed the mobilization of Tn5 on four R-primes from Bradyrhizobium japonicum I-110 and on an R-prime plasmid from Rhizobium fredii HH303. The largest R-prime plasmid was obtained from the rescue of two symbiotically defective R. fredii mutant strains that required adenosine.Non-standard abbreviation TDP transposon donor pool Scientific article number A-4728 and contribution number 7724 of the Maryland Agricultural Experiment Station     

Separation of human Fab fragments on negative mode Ni(II)-TREN-agarose chromatography

We evaluated the feasibility of using immobilized metal-ion affinity chromatography (IMAC) with nickel ion complexed with Tris(2-aminoethyl)amine (TREN) immobilized on agarose gel for purification of human Fab fragments by negative chromatography. Efficient purification of Fab fragments from digested human IgG (immunoglobulin G) (106.4% purity) was accomplished in Tris-HCl buffer at pH 7.5 without NaCl (based on total protein concentration and radial immunodiffusion of human Fab). A technological application of Ni(II)-TREN-agarose using non transgenic soybean protein extract spiked with human Fab fragments as feedstream was also studied. Experiments using Tris-HCl at pH 7.0 as loading buffer allowed the adsorption of almost all of the soybean proteins. Sixty-six percent of the loaded human Fab fragments were recovered in the flowthrough and washing fractions with about 90% purity. These results demonstrate that Ni(II)-TREN-agarose is a potential adsorbent for recombinant Fab fragment purification.     

Conditional lethality involving a cytoplasmic mutant and chlorophyll-deficient malate dehydrogenase mutants in soybean

Summary Conditional lethality in soybean, Glycine max (L.) Merr., occurred in F₂ plants when cytoplasmicchlorophyll mutant Genetic Type T275 was the female parent and when either nuclear mutants T253 or T323 plants were the male parents. Mutant T253 [Mdh1-n (Urbana) y20 (Urbana) k2] is missing two of three mitochondrial malate dehydrogenase isozymes [Mdh1-n (Urbana)] and has yellowish-green leaves [y20 (Urbana)] and a tan-saddle pattern seed coat (k2). Mutant T323 [Mdh1-n (Ames 2) y20 (Ames 2)] also is missing two of three mitochondrial malate dehydrogenase isozymes [Mdh1-n (Ames 2)] and has yellowishgreen leaves [y20 (Ames 2)], but has yellow seed coat (K2). Mutants T275, T253, and T323 are viable both in the field and glasshouse. The genotypes cyt-Y2 Mdh1-n (Urbana) y20 (Urbana) k2/Mdh1-n (Urbana) y20 (Urbana) k2 and cyt-Y2 Mdh1-n (Ames 2) y20 (Ames 2)/Mdh1-n (Ames 2) y20 (Ames 2) are conditional lethals. These genotypes are lethal under field conditions, but plants survive in reduced light under shadecloth in the glasshouse. We do not know if their interaction with cyt-Y2 is due to Mdh1-n, y20, or Mdh1-n y20. The reciprocal cross (cyt-Y2 as male parent) gives viable genotypes. These conditional lethal genotypes should be useful for studies on the interaction between organelle and nuclear genomes.This is journal paper no. J-14777 of the Iowa Agriculture and Home Economics Experiment Station, Ames, IA 50011-1010. Project 2985     

Soybean aeroallergen around the port of New Orleans: A potential cause of asthma

There have been reported epidemics of severe asthma in Barcelona, Spain, linked to a 10 kDa low molecular mass (LMM) allergen from soybean hulls that became airborne during unloading of ships. As a preliminary probe of the potential for dispersion of this allergen in USA cities, four automated air samplers were placed around a grain elevator in New Orleans and operated continuously from May to October 1990. The allergen was extracted from the filters and immunochemically assayed for soybean aeroallergen. On 31 separate days, the airborne allergen concentration in at least one of the samples was over 10000 U/m³ similar to those observed in Barcelona on some epidemic days. Areas North and East of the elevator were most affected. Serologie studies showed that of 50 asthmatics from New Orleans who were participants in an unrelated clinical study 4 or 8% demonstrated elevated titers of IgE antibody to LMM soybean allergen. Only 1 of 475 control sera (half of which were also asthmatic) obtained elsewhere in the US was positive for LMM soybean IgE antibody. Based on the findings in this study, there is a great possibility that on some days there is enough soybean allergen in the air and a sufficient frequency of soybean aeroallergen RAST positive asthmatics in New Orleans to warrant further investigation of the contribution of soybean aeroallergen to asthma around the port of New Orleans.Supported by NIAID # A121255. Mayo Clinic and Foundation and Minnesota Lung Association.     

藏区金腰种质资源调查与分析

金腰属植物因富含黄酮醇类化合物而具有显著的药效,通过对我国西藏、云南、四川、青海以及甘肃5个省(自治区)进行金腰属植物种质资源的科学考察,共收集到19种(含2变种)145份野生种质资源。此外四川省发现金腰新分布2种,分别为秦岭金腰(Chrysosplenium biondianum Engl.)、陕甘金腰(Chrysosplenium qinlingense Z.P.Jien&J.T.Pan),均为中国特有种;甘肃省发现金腰新分布3种,分别为毛金腰(Chrysosplenium pilosum Maxim.)、绵毛金腰(Chrysosplenium lanuginosum Hook.f.&Thomson)和蜕叶金腰(Chrysosplenium henryi Franch.),凭证标本存于中南民族大学植物标本馆(HSN)。金腰属植物作为传统藏药长期以来被用于治疗各种疾病,如长梗金腰(Chrysosplenium axillare Maxim.)的75%乙醇提取物具抗炎症、抗流感病毒活性,从灰花金腰(Chrysosplenium grayanum Maxim.)与裸茎金腰(Chrysosplenium nudicaule Bunge)提取的五环三萜对肿瘤细胞有较强抑制效果。本调查丰富了野生藏药金腰属植物种质资源,为深入研究金腰属植物的分类与药理活性提供了基础。     

Chromosome‐level reference genome of X12, a highly virulent race of the soybean cyst nematode Heterodera glycines

Soybean cyst nematode (SCN, Heterodera glycines) is a major pest of soybean that is spreading across major soybean production regions worldwide. Increased SCN virulence has recently been observed in both the United States and China. However, no study has reported a genome assembly for H. glycines at the chromosome scale. Herein, the first chromosome‐level reference genome of X12, an unusual SCN race with high infection ability, is presented. Using whole‐genome shotgun (WGS) sequencing, Pacific Biosciences (PacBio) sequencing, Illumina paired‐end sequencing, 10X Genomics linked reads and high‐throughput chromatin conformation capture (Hi‐C) genome scaffolding techniques, a 141.01‐megabase (Mb) assembled genome was obtained with scaffold and contig N50 sizes of 16.27 Mb and 330.54 kilobases (kb), respectively. The assembly showed high integrity and quality, with over 90% of Illumina reads mapped to the genome. The assembly quality was evaluated using Core Eukaryotic Genes Mapping Approach and Benchmarking Universal Single‐Copy Orthologs. A total of 11,882 genes were predicted using de novo, homolog and RNAseq data generated from eggs, second‐stage juveniles (J2), third‐stage juveniles (J3) and fourth‐stage juveniles (J4) of X12, and 79.0% of homologous sequences were annotated in the genome. These high‐quality X12 genome data will provide valuable resources for research in a broad range of areas, including fundamental nematode biology, SCN–plant interactions and co‐evolution, and also contribute to the development of technology for overall SCN management.