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Abstract Reference strains of ' Pseudomonas diazotrophicus ' produce a range of polar lipids atypical of authentic Pseudomonas species. In addition to the phospholipids common in Gram-negative bacteria (phosphatidylglycerol, diphosphatidylglycerol, and phosphatidylethanolamine), N -methylated derivatives of phosphatidylethanolamine (including phosphatidylcholine) and an ornithine amide lipid are also present. The preponderant ester-bound fatty acid (up to 80% of the total) is cis -vaccenic acid ( cis -octadec-11-enoic acid), while 3-hydroxyoctadecanoic acid is the major amide-bound fatty acid in the ornithine lipid. Possible implications of the data for classification of the organism are discussed.  相似文献   
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Congenital MHC class II deficiency or bare lymphocyte syndrome (BLS; McKusick 209920) is caused by defects in trans-acting regulatory factors that control MHC class II expression and is therefore a disease of gene regulation. There are at least four complementation groups and the genetic and molecular dissection of this rare disease has contributed considerably to our current understanding of the molecular mechanisms governing MHC class II expression. Identification of the gene that is defective in BLS complementation group A, CIITA (MHC class II transactivator), has led to the discovery that CIITA acts as a master control factor of MHC class II expression. We have identified the CIITA mutations in a second patient from BLS group A. Two novel mutations abolish CIITA function, as shown by transfection experiments. Molecular analysis of these two novel mutations, together with the one described earlier in the first patient, is informative in terms of CIITA structure-function relationships. Received: 19 October 1996 / Revised: 25 November 1996  相似文献   
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Wasabi (Wasabia japonica) is a unique native plant and a traditional condiment crop of Japan. It is used in traditional Japanese raw fish and noodle dishes and in several modern foods for its hot taste and tangy flavor. Japanese farmers grow the crop in wet upland orchard soils for leaves, petioles and small enlarged stems, and in flooded gravel and sand fields along streams or near springs to produce whole plants and large succulent green enlarged stems. Recent studies in Japan have demonstrated numerous enzymatic and biocidal properties of the plant. This review of Japanese and other literature details the history, uses, botany, cultivars, ecological requirements, production techniques, insect pests and diseases of wasabi.  相似文献   
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The American College of Medical Genetics and Genomics (ACMG) recommends that clinical sequencing laboratories return secondary findings in 56 genes associated with medically actionable conditions. Our goal was to apply a systematic, stringent approach consistent with clinical standards to estimate the prevalence of pathogenic variants associated with such conditions using a diverse sequencing reference sample. Candidate variants in the 56 ACMG genes were selected from Phase 1 of the 1000 Genomes dataset, which contains sequencing information on 1,092 unrelated individuals from across the world. These variants were filtered using the Human Gene Mutation Database (HGMD) Professional version and defined parameters, appraised through literature review, and examined by a clinical laboratory specialist and expert physician. Over 70,000 genetic variants were extracted from the 56 genes, and filtering identified 237 variants annotated as disease causing by HGMD Professional. Literature review and expert evaluation determined that 7 of these variants were pathogenic or likely pathogenic. Furthermore, 5 additional truncating variants not listed as disease causing in HGMD Professional were identified as likely pathogenic. These 12 secondary findings are associated with diseases that could inform medical follow-up, including cancer predisposition syndromes, cardiac conditions, and familial hypercholesterolemia. The majority of the identified medically actionable findings were in individuals from the European (5/379) and Americas (4/181) ancestry groups, with fewer findings in Asian (2/286) and African (1/246) ancestry groups. Our results suggest that medically relevant secondary findings can be identified in approximately 1% (12/1092) of individuals in a diverse reference sample. As clinical sequencing laboratories continue to implement the ACMG recommendations, our results highlight that at least a small number of potentially important secondary findings can be selected for return. Our results also confirm that understudied populations will not reap proportionate benefits of genomic medicine, highlighting the need for continued research efforts on genetic diseases in these populations.  相似文献   
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