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71.
Lactococcus lactis is a Gram-positive bacteria, which belongs to the group of lactic acid bacteria among which several genera play an essential role in the manufacture of food products. Cytosolic proteins of L. lactis IL1403 cultivated in M17 broth have been resolved by two-dimensional gel electrophoresis using two pH gradients (pH 4-7, 4.5-5.5). More than 230 spots were identified by peptide mass fingerprints, corresponding to 25% of the predicted acid proteome. The present study made it possible to describe at the proteome level a significant number of cellular pathways (glycolysis, fermentation, nucleotide metabolism, proteolysis, fatty acid and peptidoglycan synthesis) related to important physiological processes and technological properties. It also indicated that the fermentative metabolism, which characterizes L. lactis is associated with a high expression of glycolytic enzymes. Thirty-four proteins were matched to open reading frames for which there is no assigned function. The comparison at the proteome level of two strains of L. lactis showed an important protein polymorphism. The comparison of the proteomes of glucose- and lactose-grown cells revealed an unexpected link between the nature of the carbon source and the metabolism of pyrimidine nucleotides. 相似文献
72.
Intrafamilial spread of Helicobacter pylori: a genetic analysis 总被引:4,自引:0,他引:4
Roma-Giannikou E Karameris A Balatsos B Panayiotou J Manika Z Van-Vliet C Rokkas T Skandalis N Kattamis C 《Helicobacter》2003,8(1):15-20
Background. A high incidence of Helicobacter pylori among family members of children with H. pylori gastritis has previously been documented on biopsy material. The main objective of this study was the genetic clarification of H. pylori strains involved in intrafamilial dispersion. Materials and Methods. Formalin‐fixed, paraffin‐embedded material of antral mucosa from 32 members of 11 families was studied for the presence of genetic homogeneity. To achieve this goal, the entire genome of H. pylori was studied by the polymerase chain reaction (PCR)‐based random amplified polymorphic DNA (RAPD) fingerprinting method. Furthermore, the Urease A gene was analyzed using a multiplex PCR‐assay and an alternative mutation detection method based on the Hydrolink? analysis. Results. RAPD fingerprinting confirmed that closely related H. pylori strains were involved in the intrafamilial dispersion. Mutations and small deletions in Urease A gene were found in 22 out of 32 individuals. Conclusions. The homology of the H. pylori genome in members of the same family strongly supports the hypothesis of transmission of H. pylori from person‐to‐person or from a common source. 相似文献
73.
We estimated the rate of extra‐pair fertilizations (EPFs) in waved albatrosses (Phoebastria irrorata) on Isla Española, Galápagos, Ecuador, using multilocus minisatellite DNA fingerprinting. Waved albatrosses are socially monogamous, long‐lived seabirds whose main population is on Española. Aggressive extra‐pair copulation (EPC) attempts have been observed in the breeding colony during the days preceding egg‐laying. Our genetic analyses of 16 families (single chicks and their attending parents) revealed evidence of EPFs in four families. In all cases males were the excluded parent. These data suggest that waved albatrosses have an unusually high rate of EPF relative to taxa with similar life histories. Future behavioural observations will determine the extent to which forced vs. unforced EPCs contribute to this high EPF rate. 相似文献
74.
Identification of Trichoderma strains from building materials by ITS1 ribotyping, UP-PCR fingerprinting and UP-PCR cross hybridization 总被引:1,自引:0,他引:1
To study the role of Trichoderma in sick building syndrome, it is essential to be able to accurately identify species. Forty-four strains of Trichoderma spp. isolated from Danish buildings damaged by water leaks were identified using ITS1 ribotyping and universally primed PCR, UP-PCR. Ribotyping allowed the assignment of the strains into three distinct groups. High similarity of UP-PCR banding profiles of the strains allowed species designation for almost all strains (43 out of 44) when compared with the UP-PCR banding profiles obtained from reference strains of T. atroviride, T. citrinoviride, T. harzianum, T. longibrachiatum and T. viride. However, cross hybridization of UP-PCR products showed that the latter strain had high DNA homology to the ex-type strain of T. hamatum. The combined approach is a convenient way for reliable identification of Trichoderma strains. 相似文献
75.
76.
Application of denaturing gradient gel electrophoresis (DGGE) and temperature gradient gel electrophoresis (TGGE) in microbial ecology 总被引:107,自引:0,他引:107
Here, the state of the art of the application of denaturing gradient gel electrophoresis (DGGE) and temperature gradient gel electrophoresis (TGGE) in microbial ecology will be presented. Furthermore, the potentials and limitations of these techniques will be discussed, and it will be indicated why their use in ecological studies has become so important. 相似文献
77.
I. Métais C. Aubry B. Hamon D. Peltier R. Jalouzot 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1998,97(1-2):232-237
We describe the cloning and the characterization of a 130-bp DNA fragment, called OPG9-130, amplified from bean (Phaseolus vulgaris L.) genomic DNA. This fragment corresponds to a minisatellite DNA sequence containing seven repeats of 15 bp which differ
slightly from each other in their sequence. Southern analysis showed that the core sequence of 15 bp is repeated in clusters
dispersed throughout the genome. The use of this fragment as a probe allowed us to identify common bean lines by their DNA
fingerprints. We suggest that OPG9-130 will be useful for line identification as well as for the analysis of genetic relatedness
between bean species and lines.
Received: 14 February 1998 / Accepted: 10 February 1998 相似文献
78.
R. P. Adams L. H. Rieseberg 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1998,97(1-2):323-326
In order to estimate the impact of mis-coding non-homologous, co-migrating DNA bands as homologous, two sets of data were
utilized. Analyses were conducted using three Helianthus species in which each co-migrating band had previously been confirmed. Comparisons of the similarities between these three
Helianthus species using the original 177 RAPD bands and the corrected, homology verified, 197 RAPD band data set revealed that the
triangular relationship among these three species was almost identical in both data sets. The non-homology errors in the Helianthanus data sets were found to be random. These random errors merely reduced the absolute similarities, but not the relative similarities
nor the relationships among the taxa, in principal-coordinate-analysis ordination. Analyses of RAPDs for the classical Brassica U triangle were made by inserting random non-homologies for 5, 10, 15 and 20% of the original 220 RAPD bands. These analyses
revealed a progressive decrease in similarities and less loading on the first two axes in principal coordinate analysis (PCO).
However, the basic U triangle of relationships among these six Brassica species was maintained. It appears that if errors in homology of co-migrating DNA bands are random, this will have little
effect on the relative similarities and on PCO ordination. This helps explain the successful use of RAPDs at the specific
level.
Received: 6 December 1997 / Accepted: 11 December 1997 相似文献
79.
Moricandia是十字花科中唯一的具C3C4植物的属。为向十字花科芸苔属(Brasica)作物中转移C3C4等重要性状提供基本信息,从可交配性和RFLP指纹图谱两个角度研究了Moricandia与芸苔属作物间的亲缘关系。结果表明:Moricandia与芸苔属作物间的可交配性很低,仅从M.arvensis×甘蓝型油菜的105枚培养子房中获得4个杂种苗。用23个甘蓝型油菜核DNA探针和4个甜菜线粒体DNA探针检测了芸苔属作物和MoricandiaC3C4植物间DNA限制性内切酶位点多态性。Moricandia与芸苔属物种间的同源性很高,其中白菜型油菜与M.nitens之间在核基因组上的相似性甚至大于它与同属的甘蓝型油菜间的相似性。MoricandiaC3C4物种与芸苔属作物在核DNA和细胞质DNA间的高度同源性,揭示了通过有性杂交或原生质体融合及染色体间重组的途径向栽培种转移重要基因的可能性。 相似文献
80.
David L. Scott Michon D. Walker Clarence W. Clarck Channapatna S. Prakash Kenneth L. Deahl 《Plant Molecular Biology Reporter》1998,16(1):41-47
AFLP is a novel high-resolution fingerprinting method that can be used to delineate intraspecific relationships among a large variety of fungi and plants. We demonstrate that with the appropriate technical modifications, ethidium bromide staining and non-denaturing polyacryalmide minigels can be an inexpensive and time saving alternative for screening DNA samples for suitable AFLP primer pairs. Furthermore, the recovery of ethidium bromide stained polymorphic DNA fragments is not as tedious as the recovery of isotopic DNA fragments.Abbreviations: EDTA, ethylene diamine tetraacetic acid; BSA, bovine serum albumin. 相似文献