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1.
We present the nucleotide and amino acid sequence for a novel human type I hair keratin, which could be identified through its high sequence homology and strict carboxyterminal length identity as a human ortholog of the murine hair keratin mHa3. Our hHa3 sequence differs, however, from that of a previously described hHa3 hair keratin (published only as an amino acid sequence; [13]) in 24 amino acid positions, 8 of which occur in the middle of the carboxyterminal domain. PCR of genomic DNA from 25 normal human subjects using a primer pair derived from sequence segments located in the 3-region of our hHa3 clone that encode conserved amino acid sequences in both keratins, resulted in the amplification of two distinct products of 0.38 kbp and 1.0 kbp. DNA sequence analysis of the cloned PCR products allowed identification of the 0.38 kb sequence as that originating from Yuet al. [13] and the 1.0 kb sequence as that being derived from our data. The difference in fragment length was due to unique intron 6 sequences, indicating that these two keratin species are encoded by genes of their own. Moreover, extensive Southern blot analyses with DNA from 25 unrelated individuals of different races using a 3-noncoding sequence from our keratin and the intron 6 sequence of the keratin of Yuet al. [13], as hybridization probes showed that both keratin genes are present as single copy sequences occurring ubiquitously and without gross alterations in the human genome. Collectively, these data demonstrate that the human type I hair keratin described in this paper represents an isoform of the previously described hHa3 keratin. We propose that these hHa3 isoforms be named in chronological order of discovery hHa3-I and hHa3-II.  相似文献   

2.
嗜热脂肪芽孢杆菌高温蛋白酶分解毛发角蛋白的研究   总被引:2,自引:0,他引:2  
本文研究了嗜热脂肪芽孢杆菌 (Bacillusstearothermophilus)WF - 1 4 6高温蛋白酶对毛发角蛋白的水解作用。结果表明 ,在体积分数为 2 %的巯基乙醇存在的条件下 ,WF - 1 4 6高温蛋白酶对毛发角蛋白有明显的水解作用。对酶解液氨基酸分析表明 ,酶解液中含有对照液中没有的游离蛋氨酸和亮氨酸 ,且游离氨基酸总量是对照样品的 2 .4倍 ,达 1 5 8mg·L-1 。此外 ,酶解液中含有大量的肽  相似文献   

3.
A semimechanistic model has recently been proposed to explain observed correlations between the H and O isotopic composition of hair from modern residents of the USA and the isotopic composition of drinking water, but the applicability of this model to hair from non‐USA and preglobalization populations is unknown. Here we test the model against data from hair samples collected during the 1930s–1950s from populations of five continents. Although C and N isotopes confirm that the samples represent a much larger range of dietary “space” than the modern USA residents, the model is able to reproduce the observed δ2H and δ18O values given reasonable adjustments to 2 model parameters: the fraction of dietary intake derived from locally produced foods and the fraction of keratin H fixed during the in vivo synthesis of amino acids. The model is most sensitive to the local dietary intake, which appears to constitute between 60% and 80% of diet among the groups sampled. The isotopic data are consistent with a trophic‐level effect on protein H isotopes, which we suggest primarily reflects mixing of 2H‐enriched water and 2H‐depleted food H in the body rather than fractionation during biosynthesis. Samples from Inuit groups suggest that humans with marine‐dominated diets can be identified on the basis of coupled δ2H and δ18O values of hair. These results indicate a dual role for H and O isotopic measurements of keratin, including both biological (diet, physiology) and environmental (geographic movement, paleoclimate) reconstruction. Am J Phys Anthropol, 2009. © 2009 Wiley‐Liss, Inc.  相似文献   

4.
We report isotopic data (δ2H, δ18O n = 196; δ13C, δ15N n = 142; δ34S n = 85) from human hair and drinking water (δ2H, δ18O n = 67) collected across China, India, Mongolia, and Pakistan. Hair isotope ratios reflected the large environmental isotopic gradients and dietary differences. Geographic information was recorded in H and O and to a lesser extent, S isotopes. H and O data were entered into a recently developed model describing the relationship between the H and O isotope composition of human hair and drinking water in modern USA and pre‐globalized populations. This has anthropological and forensic applications including reconstructing environment and diet in modern and ancient human hair. However, it has not been applied to a modern population outside of the USA, where we expect different diet. Relationships between H and O isotope ratios in drinking water and hair of modern human populations in Asia were different to both modern USA and pre‐globalized populations. However, the Asian dataset was closer to the modern USA than to pre‐globalized populations. Model parameters suggested slightly higher consumption of locally producedfoods in our sampled population than modern USA residents, but lower than pre‐globalized populations. The degree of in vivo amino acid synthesis was comparable to both the modern USA and pre‐globalized populations. C isotope ratios reflected the predominantly C3‐based regional agriculture and C4 consumption in northernChina. C, N, and S isotope ratios supported marine food consumption in some coastal locales. N isotope ratios suggested a relatively low consumption of animal‐derived products compared to western populations. Am J Phys Anthropol 2010. © 2009 Wiley‐Liss, Inc.  相似文献   

5.
Hair from mice bearing the dominantly inherited Naked trait (NN) and from normal (NN) mice of the same inbred strain was separated into its major protein components by standard techniques. The relative amounts of proteins in these components were then determined by a regression method from the amino acid composition of the hair samples and of the fractions into which they had been separated. The results indicated that the amount of soluble fibril in Naked-mouse hair is decreased. Polyacrylamide-gel electrophoresis of this fraction prepared from the hair of both normal and Naked mice revealed that all protein bands present in the normal are also present in the Naked mice. However, a densitometric scan of the gels at 280 nm showed that the soluble fibril fraction from Naked-mouse hair is deficient in several proteins which, on amino acid analysis, were found to contain 31% glycine and 10% tyrosine. Gel filtration of S-carboxymethylkerateine prepared from normal and mutant hair showed that the mutant hair is deficient in a heterogeneous, low-molecular-weight fraction also rich in glycine and tyrosine. Our present data do not reveal the mechanism whereby a single gene locus modulates the production of several different proteins.  相似文献   

6.
Summary A previously described electron histochemical method for detecting cystine in fully keratinised human hair has been modified for the examination of this amino acid residue amongst the cellular components of anagen guinea pig hair follicles. Using the technique the progressive incorporation of cystine into the hair cuticle and cortex has been observed. Although cystine was absent from the hair medulla and outer root sheath cells at all stages of development, a narrow layer of cystine-containing material was found adjacent to the cell membranes of hardened inner root sheath cells.  相似文献   

7.
猪毛酸解提取胱氨酸母液中,含有17种游离氨基酸。采用酒精析出法,提取了氨基酸,同时采用质谱场解析法证实了还存在小分子肽类物质,它将可在日用化工工业中作为助剂应用。  相似文献   

8.
角蛋白71(Keratins 71,KRT71)属于人类Ⅱ型上皮角蛋白,是毛囊特异性的上皮角蛋白基因。相关研究表明,在其他物种中,KRT71与被毛卷曲相关,KRT71在卷曲的被毛形成过程中起着重要的作用。现眼观羊驼背部、耳部和腿部毛发的弯曲程度不同,但KRT71与其被毛的弯曲度是否相关尚不清楚。本研究利用PCR技术克隆KRT71基因全CDS区。通过实时荧光定量PCR技术检测基因的表达。免疫组化、Western 印迹对KRT71蛋白在羊驼背部、耳部和腿部皮肤组织中的表达量进行分析,以探讨KRT71与羊驼毛发弯曲度的关系。结果显示,羊驼的KRT71基因的CDS区共有1 578 bp,编码525个氨基酸;免疫组化结果显示,KRT71在羊驼的背部、耳部和腿部均有表达,并且主要特异性表达于毛囊的内根鞘;实时荧光定量PCR和Western印迹结果显示,KRT71的mRNA和蛋白量均呈现背部﹥腿部﹥耳部的趋势;相较于耳部,背部和腿部的表达量较高。实验结果提示,KRT71的表达量与毛纤维的弯曲度呈正相关,KRT71可能在羊驼毛纤维的弯曲度形成过程中发挥着一定的作用。  相似文献   

9.
Cao J  Wijaya R  Leroy F 《Biopolymers》2006,83(6):614-618
An attempt has been made to obtain intact individual keratin filaments of various levels from micron cortical, micron macrofibril to nano intermediate filament and polypeptide alpha-helix from the human hair shaft. The feasibility of this initiative has been largely demonstrated by finding that there is a longitudinal seam/zipper on the cuticle of the human hair shaft, which can be unzipped by certain solvents such as performic acid and urea, allowing one to use an anatomical approach to separate intact individual micron/nano filaments. Micron cortical and macrofibril filaments have been obtained. It is also found that the cortical filaments are twisted together to form a yarn, giving rise to the strength for the hair shaft; and that individual cortical filaments are often 2-2 paired in a similar structure to the double helix.  相似文献   

10.
Isoelectric focusing of extracted keratin not S-carboxymethylated followed by silver staining was used in this study with the attempt to identify head hair keratins from different racial groups: Guatuso and Caribbean (Costa Rica, America), Balanta (Guinea-Bissau, Africa) and Sardinian (Italy, Europe). Morphological analysis of hair and quantitation of solubilized total proteins were also performed. Keratins extracted from hair gave similar IEF patterns for all samples in the ranges of pH 4.5–5.0 and 5.4–7.4, differing only in the intensity and width of the bands. IEF patterns for Guatuso samples differ from all the others in the presence of some additional bands in the range of pH 4.0–4.5. Different electrophoretic patterns are not associated with detectable differences in the morphology of the fibers. It seems to us that electrophoretic techniques may be useful in the identification of hair from different racial groups.  相似文献   

11.
Kuzuhara A  Hori T 《Biopolymers》2005,79(6):324-334
In order to investigate the reduction mechanism of L-cysteine (Cys) on keratin fibers, cross-sectional samples of virgin white human hair treated with Cys were prepared. The heterogeneous reaction between Cys and keratin fibers involving the diffusion of Cys into human hair was analyzed at the molecular level using microspectrophotometry and Raman spectroscopy. The diffusion pattern of Cys into human hair showed non-Fickian type characteristics, thus indicating the free amino groups of electrostatically interacted with the anionic ions of the fiber surface. The disconnected relative concentration of -SS- groups at various depths of the hair samples with pH 9.0 was less than the Cys relative concentration, indicating that the reaction rate (the disconnection of -SS- groups) was slower than the diffusion rate of Cys into human hair. From these experiments, we concluded that the free amino groups of Cys electrostatically interacted with the anionic ions of the fiber surface, thereby decreasing the reaction rate (the disconnection of -SS- groups) of Cys at pH 9.0.  相似文献   

12.
Bluegill-degrading bacteria were isolated from various environmental sources. Brevibacillus sp. BGM1 degraded bluegill efficiently at 50 degrees C, and its culture supernatant showed the highest peptide and amino acid concentrations as trichloroacetic acid (TCA) soluble fraction (ASF) (10.7 mg/ml) of all supernatants obtained with bluegill as a substrate. Strain BGM1 secreted a protease(s) into the medium, and the concentration of peptides and amino acids gradually increased. The fertile effect of the degraded bluegill products (DGP) on Brassica rapa was also investigated. The root hair density of B. rapa grown with DGP at a concentration of 30 mug peptides and amino acids/ml was about 1.7 times higher than when grown with the same concentration of undegraded bluegill. DGP was shown to increase root hair numbers and adventitious root formation. The results of this study suggest that a specific peptide(s) for promotion of root hair is produced from the order Perciformes with a protease(s) from BGM1.  相似文献   

13.
Aims:  To determine the ability of a novel Bacillus subtilis AMR isolated from poultry waste to hydrolyse human hair producing peptidases including keratinases and hair keratin peptides.
Methods and Results:  The Bacillus subtilis AMR was identified using biochemical tests and by analysis of 16S rDNA sequence. The isolate was grown in medium containing human hair as the sole source of carbon and nitrogen. The supplementation of hair medium (HM) with 0·01% yeast extract increased the keratinolytic activity 4·2-fold. B. subtilis AMR presented high keratinase production on the 8th day of fermentation in hair medium (HM) supplemented with 0·01% yeast extract (HMY) at pH 8·0. Keratinase yield was not correlated with increase in biomass. Zymography showed keratin-degrading peptidases migrating at c. 54, 80 and 100 kDa and gelatin-degrading bands at c. 80, 70 63, 54 32 and 15 kDa. Keratinases were optimally active at 50°C and pH 9·0 and was fully inhibited by the serine proteinase inhibitor (PMSF). Scanning electron microscopy showed complete degradation of the hair cuticle after exposure to B. subtilis AMR grown in HMY. MALDI-TOF analysis of culture supernatant containing peptides produced during enzymatic hydrolysis of hair by B. subtilis AMR revealed fragments in a range of 800–2600 Da.
Conclusions:  This study showed that B. subtilis AMR was able to hydrolyse human hair producing serine peptidases with keratinase and gelatinase activity as well as hair keratin peptides.
Significance and Impact of the Study:  This is the first report describing the production and partial characterization of keratinases by a B. subtilis strain grown in a medium containing human hair . These data suggest that peptides obtained from enzymatic hair hydrolysis may be useful for future applications on pharmaceutical and cosmetic formulations.  相似文献   

14.
Kuzuhara A 《Biopolymers》2006,81(6):506-514
To investigate the influence of bleaching treatments on keratin fibers, the structure of cross-sections at various depths of bleached human hair (black and white human hair) was directly analyzed without isolating the cuticle and cortex, using Raman spectroscopy. The S-S band intensity existing from the cuticle region to the center of cortex region of virgin white human hair decreased, while the S-O band intensity at 1040 cm(-1), assigned to cysteic acid, increased by performing the bleaching treatment. Especially, the S-O band intensity of the cuticle region increased remarkably compared with that of the cortex region. Also, the amide III (unordered) band intensity in the cortex region increased, indicating that some of the proteins existing throughout the cortex region changed to the random coil form. Moreover, it has been found that the S-S band intensity existing from the cuticle region to the center of the cortex region of the virgin black human hair decreased remarkably, while the S-O band intensity increased significantly compared with that of the virgin white human hair by performing the bleaching treatment. From these experiments, we concluded that the melanin granules including metal ions act as a decomposition accelerator for the oxidizing agent, thereby leading to a higher level of disulfide (-SS-) group cleavage in the black human hair compared with that of the white human hair.  相似文献   

15.
The claw of lizards is largely composed of beta‐keratins, also referred to as keratin‐associated beta‐proteins. Recently, we have reported that the genome of the lizard Anolis carolinensis contains alpha keratin genes homologous to hair keratins typical of hairs and claws of mammals. Molecular and immunohistochemical studies demonstrated that two hair keratin homologs named hard acid keratin 1 (HA1) and hard basic keratin 1 (HB1) are expressed in keratinocytes forming the claws of A. carolinensis. Here, we extended the immunocytochemical localization of the novel reptilian keratins to the ultrastructural level. After sectioning, claws were subjected to immunogold labeling using antibodies against HA1, HB1, and, for comparison, beta‐keratins. Electron microscopy showed that the randomly organized network of tonofilaments in basal and suprabasal keratinocytes becomes organized in long and parallel bundles of keratin in precorneous layers, resembling cortical cells of hairs. Entering the cornified part of the claw, the elongated corneous cells fuse and accumulate corneous material. HA1 and HB1 are absent in the basal layer and lower spinosus layers of the claw and are expressed in the upper and precorneous layers, including the elongating corneocytes. The labeling for alpha‐keratin was loosely associated with filament structures forming the fibrous framework of the claws. The ultrastructural distribution pattern of hard alpha‐keratins resembled that of beta‐keratins, which is compatible with the hypothesis of an interaction during claw morphogenesis. The data on the ultrastructural localization of hair keratin homologs facilitate a comparison of lizard claws and mammalian hard epidermal appendages containing hair keratins. J. Morphol., 2011. © 2010 Wiley‐Liss, Inc.  相似文献   

16.
We present here a 1770 bp-long cDNA which encodes a murine type II keratin. Sequence comparisons of the keratin with those of various type II keratins expressed in mouse epidermis and internal stratified epithelia reveal that the new keratin is unrelated to epithelial keratins. Rather the structural organization of its amino- and carboxyterminal domains and the high content of cysteine and proline residues in these regions suggest that the keratin represents a murine type II hair keratin. This assumption was confirmed by in situ hybridization which localized the mRNA of the keratin in upper cells of the hair cortex and in suprabasal cells of the central core unit of filiform papillae of the tongue. Hybrid selection analyses revealed that the keratin has a molecular weight of 58 kD. It remains to be seen whether the keratin corresponds to MHb 3 or MHb 4.  相似文献   

17.
Cell membrane complex preparations have been extracted using formic acid from human hair and nail, and from the hair of sheep, alpaca, rabbit, rat, cat, and dog. On analysis they were found to have similar amino acid compositions and they all contained carbohydrate. The sugars were typical of those found in membrane glycoproteins and all preparations reacted with peroxidase-conjugated lectins.  相似文献   

18.
1. S-Carboxymethylkerateines extracted from normal hair can be fractionated into high-sulphur and low-sulphur proteins similar to those obtained from sheep's wool. Normal human hair gives a major high-sulphur protein of higher molecular weight and S-carboxymethylcysteine content than any isolated from normal sheep's wool. 2. The proteins from cystine-deficient hair can also be divided into high-sulphur and low-sulphur proteins. There is a lower proportion of high-sulphur protein in cystine-deficient hair than in normal hair. 3. The high-sulphur proteins from cystine-deficient hair have an abnormal amino acid composition and in particular are lower in S-carboxymethylcysteine content than the corresponding proteins from normal hair. New components are present and the content of very high-sulphur proteins of high molecular weight is much decreased. The low-sulphur proteins of cystine-deficient hair are probably also deficient in S-carboxymethylcysteine. 4. The proteins of cystine-deficient hair probably resemble those in the normal hair root, except that disulphide-bridge formation has occurred.  相似文献   

19.
昆明小鼠无毛基因cDNA全长序列的分子克隆   总被引:2,自引:0,他引:2  
章金涛  方盛国  王纯耀  杜春燕 《遗传》2005,27(6):908-914
无毛基因是与皮肤和被毛结构有重要关联的核受体基因,编码一个锌指结构转录因子,是甲状腺激素受体的转录辅阻遏物,并参与毛发生长周期的调控,在维持毛囊及毛囊间上皮的增殖、分化、调亡的精致平衡中扮演重要角色。参考小鼠、人的无毛基因序列,用RT-PCR方法首次对昆明小鼠无毛基因的cDNA序列进行了克隆,获得了昆明小鼠无毛基因的全长4 014 bp cDNA序列(GenBank 登录号:AY547391),基因的CDS长度为3 546 bp。AY547391基因编码的蛋白质在GenBank中的序号为AAT45233,由1181个氨基酸组成。昆明小鼠与国外报导的小鼠、大鼠、猪、羊、猴、人等6种动物CDS 序列同源性分别为99.9%、94.4%、83.1%、78.1%、81.9%、82.1%,氨基酸同源性分别是99.9%、92.2%、81.7%、 70.8%、 79.9%、 80.1% 。这一结果反应了无毛基因在进化过程的高度保守性。通过Blast比较昆明小鼠无毛基因与GenBank 数据库中收集的Hr 基因的mRNA,发现了4个SNP和一个缺失突变,其中3个位点没有改变氨基酸残基的性质,两个位点有氨基酸改变并证实为多态性突变位点,研究结果为无毛基因的SNPs的数据库提供了新的信息。  相似文献   

20.
Air-dried cow hair was treated using Ca(OH)(2) (insoluble in water but dissolved during reaction) at 100 degrees C. To obtain a liquid product rich in amino acids, a well-insulated, stirred reactor was used to perform the hydrolysis process for different time periods. High lime loadings and a long treatment period convert 70% of cow hair to soluble amino acids and polypeptides. Protein solubilization varies with lime loading especially for the long-term treatment (t>12h) showing that the hydroxyl group is required as a catalyst for the hydrolysis reaction and that lime is consumed during the process; as a consequence lower lime loading generate lower conversions. A very perceptible ammonia odor in the soluble product suggests amino acid degradation. Arginine, threonine, and serine are the more susceptible amino acids under alkaline hydrolysis. The amino acid composition of the solubilized product compares poorly with the essential amino acid requirements for various monogastric domestic animals, but it has value as ruminant feed.  相似文献   

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