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1.
J. Hojný 《Animal genetics》1973,4(3):161-168
The haemolytic reagent allowing direct serological detection of He homozygous pigs was obtained by the immunization of a Landrace sow. Another monospecific reagent prepared from immune serum of a Miniature pig made possible the evidence for a new factor of the H system - He. This factor is genetically controlled by the allele H be. Its frequency in Miniature pigs was 0.099.
The H system with alleles H 1=Ha, H2= Hb, H3= Hab, H4=Hcd, H5= Hbd, H6=Hbe and H7= H- continues to be a genetically open system.  相似文献   

2.
In Leghorn (laying) chickens, susceptibility to a number of infectious diseases is strongly associated with the major histocompatibility ( B ) complex. Nucleotide sequence data have been published for six class I ( B-F ) alleles and for class II ( B-Lβ ) alleles or isotypes from 17 Leghorn haplotypes. It is not known if classical B-L or B-F alleles in broilers are identical, at the sequence level, to any Leghorn alleles. This report describes molecular and immunogenetic characterization of two haplotypes from commercial broiler breeder chickens that were originally identified by serology as a single haplotype, but were differentiated serologically in the present work. The two haplotypes, designated B A4 and B A4variant, shared identical B-G restriction fragment length polymorphism patterns, but differed in one B-Lβ fragment that cosegregated with the serological B haplotype. Furthermore, the nucleotide sequences of the highly variable exons of an expressed B-LβII family gene and B-F gene from the two haplotypes were markedly different from each other. Both the B-LβII family and B-F gene sequences from the B A4 haplotype were identical to the sequences obtained from the reference B 21 haplotype in Leghorns; however, in the B A4 haplotype the B-Lβ 21 and B-F 21 alleles were in linkage with B-G alleles that were not G 21. The nucleotide sequences from B A4variant were unique among the reported chicken B-LβII family and B-F alleles.  相似文献   

3.
Two new erythrocyte antigens have been detected by isoimmune antibodies obtained from Gottingen Miniature pigs. By family studies they proved to belong to the E system. The factor designated En is genetically controlled by alleles E 2= E edghkmn, E 3= E aegln, E 4= E edfhkmn, E 6= E aefln, E 9= E edghjmn, E 12= E aegmno and E edgkln, and the factor designated Eo by the allele E 12= E aegmno.
The En blood factor occurs in all the breeds studied and in frequency it comes close to a related Ee factor. It stands in opposition not only to Eb but also to Ei factor. The Eo factor can be characterized as a rarely occurring Ea subgroup. Besides being antithetic to Ed it is also antithetic to El and Ei factors. For the present, it was found only in Miniature pigs.  相似文献   

4.
So far, at least eight alleles in the goat CSN2 locus have been associated with the level of β -casein expression in milk. Alleles CSN2 A , CSN2 A 1, CSN2 B , CSN2 C , CSN2 D and CSN2 E have been associated with normal content (allele effects of about 5 g of β -casein per litre), whereas the CSN2 0 and CSN2 01 alleles have been associated with non-detectable levels of β -casein. Most of these alleles have been characterized genetically. Herein, we report the identification of a previously unreported SNP in the goat CSN2 promoter region ( AJ011018 :g.1311T>C), which is associated with the absence of β -casein in the milk. Furthermore, we developed a PCR-based method that allows detection of this mutation.  相似文献   

5.
A genetic polymorphism of the pig amylase 2 system is described. It is controlled by two codominant genes, Am 2A and Am 2B. A comparison of some breeds from Byelorussian breeding farms gives the following frequencies for the alleles Am 2A and Am 2B , respectively: 0.35 and 0.865 in Large White (n = 682), 0.257 and 0.743 in Byelorussian Black and White (n = 400), 0.540 and 0.460 in Hampshire (n = 51).
While studying the genotype distribution according to the Hardy-Weinberg law, a genetic imbalance in Byelorussian Black and White pigs was established (χ2= 56.4). Genetic relationship between the Am 1 and Am 2 loci was not found.  相似文献   

6.
Identification of full length genes along with upstream regulatory elements is important to understand its expression. Here, we report preparation of high titre genomic library and identification of a genomic clone containing Pi-k h gene with its complete upstream and downstream sequences from the rice blast resistant line Tetep. Structural analysis of protein revealed that Pi-k h has a central nucleotide binding site domain, leucine-rich repeats domain and a unique zinc-finger domain. Comparative analysis of Pi-k h protein sequence showed 64% and 45% similarity with the protein sequences of rice blast resistance genes Pi-b and Pi-ta , respectively.  相似文献   

7.
The capacity of Lettuce mosaic virus to overcome the lettuce resistance conferred by the mo11 and mo12 alleles of the gene for eukaryotic translation initiation factor 4E (eIF4E) was analysed using reverse genetics. Mutations in the virus genome-linked protein (VPg) allowed mo11 only to be overcome, but mutations in the C-terminal portion of the cylindrical inclusion (CI) protein allowed both alleles to be overcome. Site-directed mutagenesis pinpointed a key role of the amino acid at position 621 in the virulence. This is the first example of the involvement of a potyviral CI protein in the breaking of an eIF4E-mediated resistance.  相似文献   

8.
EnvC, a new lipoprotein of the cytoplasmic membrane of Escherichia coli   总被引:5,自引:0,他引:5  
Abstract A gene product with an apparent molecular mass of approximately 39000 Da can be identified in the cytoplasmic membrane of Escherichia coli upon expression of cloned envC . In this communication we report that the product was labelled with [3H]glycerol and [3H]palmitic acid, and a precursor molecule of increased molecular mass was accumulated when cells were treated with globomycin, a specific inhibitor for the prolipoprotein signal peptidase. The same precursor molecule was encoded by an envC mutant gene, in which the cysteine residue in a pentapeptide sequence, Leu-Ile-Ala-Gly-Cys24 within the amino terminal region of EnvC, was replaced by tryptophane (Trp24). This protein was not labelled with [3H]glycerol. The results demonstrate that the envC gene product represents a new lipoprotein of the cytoplasmic membrane of E. coli .  相似文献   

9.
Physiological mechanisms of buoyancy in eggs from brackish water cod   总被引:2,自引:0,他引:2  
Newly fertilized eggs of brackish water (Gotland, Baltic Sea) and marine (Lofoten, Norway) cod were investigated with regard to specific gravity, wet and dry weight, water content, chorion weight, and content of protein, free amino acids (FAA), and ions. The eggs had neutral buoyancies equivalent to a salinity of 14.3% (range 11.5–16.2%) in brackish water, and 33.0% (range 31.8–34.5%) in the marine environment. A buoyancy model was developed and showed that this difference was mainly caused by differences in egg water content which was 96.6 ± 0.47% and 92.7 ± 0.45% in the brackish and marine eggs, respectively. The higher water content of the brackish eggs resulted from increased water uptake during final oocyte maturation due to higher intracellular contents of FAA, Cl and NH4+. SDS polyacrylamide gel electrophoresis of eggs and oocytes, and measurements of egg protein content suggested that the FAA pool of both egg types originated from hydrolysis of specific yolk proteins. The main contributor seemed to be a protein with a molecular weight of 100 kDa.  相似文献   

10.
Abstract The relationship between the cytotoxic effect and binding to different cell lines of Clostridium perfringens enterotoxin was investigated. The enterotoxin released 51Cr from Vero and MDCK cells labeled with Na2-51CrO4. The effect varied depending upon the dose of enterotoxin and the duration and temperature of the interaction. The enterotoxin gave no effect on FL, KB, or L-929 cells. [125I]Enterotoxin bound specifically to Vero and MDCK cells via a binding site of distinct nature, but not to FL, KB, or L-929 cells. The number of the binding sites located on one MDCK cell (1.98 × 106 sites/cell) was three times that on one Vero cell (5.64 × 105 sites/cell), although the binding affinity of MDCK cell ( K a/ 3.76 × 107 M−1) was 0.1 that of Vero cells ( K a/ 3.23 × 108 M−1). Binding of the enterotoxin to susceptible cells was temperature-independent.  相似文献   

11.
Summary
Using agarose gel isoelectric focusing and immunoblotting with rabbit anti-rabbit C6, a genetic polymorphism has been found in the sixth component of complement (C6) in six breeds of pigs. The C6 locus was highly polymorphic. Family data indicated that pig C6 pheno-types were inherited by means of five codomonant alleles named C6 A, C6 B, C6 C, C6 D and C6 E at a single autosomal locus. C6 deficiency in two of 241 individuals tested was found, which suggested the presence of a null allele in pig populations. Marked breed differences among the gene frequencies and heterozygosities at C6 locus were observed.  相似文献   

12.
W.G. VAN DOORN AND K. D'HONT. 1994. Flowering stems of four rose cultivars (Sonia, Madelon, Jacaranda and Frisco) were placed in aqueous suspensions of bacteria at 104 and 108 colony-forming units (cfu) ml-1 for 24 h at 5C, then stored dry or held in water for 24 h at 8C and subsequently placed in vase-water at 20C. The effects of these treatments on vase-water uptake were similar to the effects on flower opening. In Sonia and Madelon roses flower opening was negatively affected both by 108 cfu ml-1 of bacteria and by dry storage. No effect was found at 104 cfu ml-1, but this concentration had a detrimental effect on flower opening when combined with dry storage. Although flower development in Jacaranda roses was not affected by the bacteria treatments it was inhibited by dry storage. This inhibition was progressively greater when the stems had previously been pulse-treated with a larger number of bacteria. Flower opening in Frisco roses was not affected by even the highest concentration of bacteria, nor by the period of dry storage. It is concluded that placing flowers in water containing bacteria (up to 108 cfu ml-1) may not always have a negative effect on flower development in cut rose flowers but, together with the effects of dry storage, the presence of even a low number of exogenous bacteria (104 cfu ml-1) inhibits the development in several cultivars. Such bacterial counts are nearly always found in samples of water used for standing roses during distribution to the consumers.  相似文献   

13.
14.
1. Growth, density and δ13C of wood and leaf area were measured in two adjacent stands of 6 year-old Eucalyptus globulus growing in the 600–700 mm year–1 rainfall region of south-western Australia. Study sites were identical except for differences in the availability of water owing to physical properties of soil profiles and location of sites within the landscape.
2. Abundance of 13C (expressed as δ13C) in wood of trees growing on the drought-prone site (– 24·8‰±1·4) was greater than in other trees (– 25·8‰±1·2, P <0·001) throughout the 6 years and, with further development, the δ13C signatures of wood may become useful indices of drought-susceptibility in plantations within a few years of establishment. The seasonal pattern of δ13C of wood appeared to reflect seasonal variation in water availability and duration of cambial activity.
3. Basic density of wood of trees growing on the more drought-prone site (496±14·0 kg m–3) was reduced compared to other trees (554±5·3 kg m–3, P <0·001). δ13C of wood across boundaries of growth-rings suggested that drought stopped cambial activity resulting in less production of late wood and less dense wood.
4. The stand growing on the drought-prone site had reduced growth, wood yield and leaf area but identical specific leaf area. Annual growth was correlated with the previous season's rainfall. Together, these results suggested that within the same evaporative climate, drought reduces growth primarily by reducing leaf area and that there is a lag between onset of drought and reduced productivity.  相似文献   

15.
Abstract The biosynthesis of the positional isomers of the monounsaturated fatty acids of Methylococcus capsulatus (Bath) has been investigated by studying the incorporation of [2-14C]malonyl CoA into long-chain fatty acids in vitro. The major unsaturated products were Δ 9 16:1 and Δ 11 18:1; however, Δ 8, Δ 10 and Δ 11 16:1, as well as, Δ 10, Δ 12 and Δ 13 18:1 were also synthesized. The exclusion of O2 from the reaction vessel did not affect the synthesis of unsaturated fatty acids or the double bonds positions. Cerulenin inhibited the synthesis of unsaturated fatty acid more than saturated fatty acid. The use of both [1-14C] octanoate and [1-14C] decanoate as substrate resulted in the synthesis of long-chain fatty acids, however, unsaturates were only synthesized from octanoate. These results imply that the unique positional isomers of M. capsulatus are not synthesized by an aerobic mechanism.  相似文献   

16.
17.
Rapid identification and detection of Oenococcus oeni was achieved by species-specific PCR. Two primers flanking a 1025 bp region of the O. oeni gene encoding the malolactic enzyme were designed. The expected DNA amplificate was obtained only when purified DNA from O. oeni was used. The identity of PCR product was confirmed by nested PCR and restriction analysis. Within 8 h, 103 cfu ml−1 of oenococci were detected in fermenting grape must containing 107 yeast cells, whereas the detection limit in wine was 104 cfu ml−1. The rapidity and reliability of the PCR procedure established suggests that the method may be profitably applied in winery laboratories for quality control.  相似文献   

18.
A method for genotyping K-casein ( A, B, E ), β-casein ( A 1, A 2, A 3, A5, B ) and β-lactoglobulin ( A, B ) simultaneously by the use of allele discrimination by primer length combined with automated detection of fragments with a sequencing instrument is described. Seven different mutations within the milk protein genes were analysed in order to distinguish between the alleles examined. The samples were amplified in two separate multiplex polymerase chain reactions (PCRs), which were then pooled and separated according to size in a single lane on the gel. By using stringent PCR conditions, we have been able to achieve allele-specific amplifications and minimize amplification of mismatched primer for all seven mutations.  相似文献   

19.
The sludge from hospital waste treatment facilities is a potential source of infectious organisms. The average numbers of micro-organisms in the sludge of hospital wastewater in Taiwan were as follows: total count 8·1 × 107 cfu g−1 (dry weight of sludge), and 1·4 × 106, 3·6 × 105, 1·6 × 105, 2·2 × 105 and 5·5 × 104 cfu g−1 (dry weight of sludge) for total coliforms, faecal coliforms, faecal streptococci, Pseudomonas aeruginosa and Salmonella spp., respectively . Salmonella spp. were detected in 37% (10 of 27) of the sludges from hospital wastewaters. Therefore, the treatment of such sludge to reduce pathogenic micro-organisms should be considered.  相似文献   

20.
Polyclonal antisera made in rabbits against whole washed cells of Vibrio pelagius and Aeromonas caviae were used for detection of these bacterial species in the rearing water and gastrointestinal tract of healthy turbot ( Scophthalmus maximus ) larvae exposed to V. pelagius and/or Aer. caviae . The results demonstrated that this method is suitable for detection of V. pelagius and Aer. caviae in water samples and larvae at population levels higher than 103 ml−1 and 103 larva−1. Populations of aerobic heterotrophic bacteria present in the gastrointestinal tract of turbot larvae, estimated using the dilution plate technique, increased from approximately 4 × 102 bacteria larva−1 on day 3 post-hatching to approximately 105 bacteria fish−1 16 days post-hatching. Sixteen days after hatching, Vibrio spp. accounted for approximately 3 × 104 cfu larva−1 exposed to V. pelagius on days 2, 5 and 8 post-hatching. However, only 103 of the Vibrio spp. belonged to V. pelagius . When larvae were exposed to Aer. caviae on day 2 post-hatching, the gut microbiota of 5-day old larvae was mainly colonized by Aeromonas spp. (104 larva−1), of which 9 × 103 belonged to Aer. caviae . Later in the experiment, at the time when high mortality occurred, 9 × 105 Aer. caviae were detected. Introduction of V. pelagius to the rearing water seemed to improve larval survival compared with fish exposed to Aer. caviae and with the control group. It was therefore concluded that it is beneficial with regard to larval survival to introduce bacteria ( V. pelagius ) to the rearing water.  相似文献   

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