排序方式: 共有33条查询结果,搜索用时 15 毫秒
1.
Two full-length (or nearly so) cDNA clones containing information for the protease inhibitors PI IV and C-II from soybean seeds were identified by means of a synthetic probe. DNA sequencing revealed that the two protease inhibitors are synthesized as precursors with a short peptide leader. The coding regions of the two clones show 80% homology, wheraes the 5 non-coding regions are 90% homologous. Homology of 75% is found in the region extending beyond the stop codons. 相似文献
2.
Mao Y Lai C Vogtentanz G Schmidt B Day T Miller J Brandon DL Chen D 《The protein journal》2005,24(5):275-282
Monoclonal antibodies against soybean Bowman-Birk protease inhibitor (BBI) have been generated and used to detect and quantify
BBI in foods, soybean germplasm, and animal tissues and fluids. The purpose of this study was to determine the recognition
sites of two monoclonal antibodies to BBI (mAb 238 and mAb 217) in relation to the protease-inhibitory sites of BBI. The results
showed that (1) the binding of mAb 238 can be blocked by trypsin and that of mAb 217 by chymotrypsin; (2) the trypsin or chymotrypsin
inhibitory activities of BBI are blocked by mAb 238 or mAb 217, respectively; and (3) mAb 238 failed to recognize a tryptic
loop mutant BBI variant and mAb 217 was unable to bind a chymotryptic loop mutant BBI variant. These findings demonstrate
that the epitopes recognized by mAb 238 and mAb 217 reside, at least in part, in the tryptic and chymotryptic loops of BBI,
respectively. 相似文献
3.
Structural features and molecular evolution of Bowman-Birk protease inhibitors and their potential application 总被引:3,自引:0,他引:3
The Bowman-Birk inhibitors (BBIs) are well-studied serine protease inhibitors that are abundant in dicotyledonous and monocotyledonous plants. BBIs from dicots usually have a molecular weight of 8k and are double-headed with two reactive sites, whereas those from monocots can be divided into two classes, one approximately 8 kDa in size with one reactive site (another reactive site was lost) and the other approximately 16 kDa in size with two reactive sites. The reactive site is located at unique exposed surfaces formed by a disulfide-linked β-sheet loop that is highly conserved, rigid and mostly composed of nine residues. The structural features and molecular evolution of inhibitors are described, focusing on the conserved disulfide bridges. The sunflower trypsin inhibitor-1 (SFTI-1), with 14 amino acid residues, is a recently discovered bicyclic inhibitor, and is the most small and potent naturally occurring Bowman-Birk inhibitor.Recently, BBIs have become a hot topic because of their potential applications. BBIs are now used for defense against pathogens and insects in transgenic plants, which has advantages over using toxic and polluting insecticides. BBIs could also be applied in the prevention of cancer, Dengue fever, and inflammatory and allergic disorders, because of their inhibitory activity with respect to the serine proteases that play apivotal role in the development and pathogenesis of these diseases. The canonical nine-residue loop of BBIs/STH-1 provides an ideal template for drug design of specific inhibitors to target their respective proteases. 相似文献
4.
S. Anandhan Insaf A. Qureshi K. R. Koundal 《Physiology and Molecular Biology of Plants》2010,16(1):31-37
The bowman-birk type trypsin inhibitors accumulate in high concentration in legume and cereal seeds, especially during seed maturation and are considered to be involved in insect tolerance. The 5′ flanking sequences of the trypsin inhibitor was isolated from cowpea genomic DNA using anchor PCR. Analysis of sequences showed presence of seed specific RY elements and also other elements associated with seed development such as abscisic acid responsive elements (ABA responsive elements; ABRE) and dehydration responsive elements (DRE). Spatial and temporal control of the promoter driven expression pattern was analyzed using gus as reporter. Expression was found to occur both in embryo and endosperm; starting from torpedo stage of embryogenesis and continuing till the stage of final maturation i.e. bent cotyledon stage. Additional expression analyses showed that the promoter actually drives expression in tissues like leaves, roots, stipules, etc., but followed a specific pattern. Comparative analysis of expression in seeds and other organs indicated that the promoter driven expression is in response to cellular maturation. 相似文献
5.
A. S. Balkina A. A. Selischeva N. I. Larionova 《Biochemistry (Moscow) Supplemental Series B: Biomedical Chemistry》2009,3(1):48-53
Possibility of encapsulation of water-soluble proteins into multilayer liposomes of soybean zwitterionic phospholipid mixtures (phosphatidylcholine (PC) and phosphatidylethanolamine (PE)) was investigated. The influence of the PC/PE ratio (w/w) on efficiency of incorporation of the Bowman-Birk soybean proteinase inhibitor (BBI) and aprotinin (BPTI) into liposomes was studied. Protein encapsulation did not affect liposome sizes. Confocal laser scanning microscopy demonstrated that proteins were located in the central part of the spherical particle and also between bilayers. The study of biological (antitrypsin and antichymotrypsin) activity demonstrated partial spatial shielding of active sites of proteins entrapped in liposomes. The effect of an ionic detergent on the activity of the encapsulated BBI and BPTI is consistent with this hypothesis and suggests that this shielding is reversible. Stability of liposomes was examined using three various media modeling gastrointestinal fluids (gastric and intestinal juices and fluids). Data obtained indicate that the prepared liposomes seem to be promising formulations for BBI and BPTI delivery. 相似文献
6.
Katherine D. Collier Gudrun Vogtentanz Neelam S. Amin Melodie Estabrook David A. Estell Bryan Fox Scott D. Power Roopali Rao Brian F. Schmidt 《Protein expression and purification》2009,68(2):146-160
Replacing the chymotrypsin inhibitory loop of soybean Bowman-Birk inhibitor (sBBI) with a VEGF binding peptide (BBI-AV) significantly reduces the overall purification yield when BBI-AV is produced as a fusion protein in a Bacillus subtilis expression system. The low purification yield is primarily due to a higher fraction of molecules with incorrect disulfide bond configurations after production and also after disulfide bond shuffling induced by 2-mercaptoethanol. To improve production yields, site-saturation libraries were generated at 39 out of the 66 amino acid residues of BBI-AV. Initial screens were designed to select for variants with higher trypsin inhibitory activities than the parent after treatment with a reducing agent. Secondary screens were developed to select for variants with the highest purification yields, and to also eliminate any false positives. From the screens, it was found that positively charged substitutions in the exposed hydrophobic patch region (sites 27, 29, 40, 50 & 52) are especially productive. In fact, one substitution, F50R, improves the purification yield to nearly the same level as wild-type sBBI. Productive amino acid substitutions were combined to select for the variant with the best overall yield after purification. Several variants were obtained with higher purification yields than even sBBI. The octuple variants, A13I-S25R-M27A-L29P-S31A-A40H-F50K-V52T and A13I-S25K-M27A-L29R-S31E-A40K-F50Q-V52Q, are particularly productive having greater than a five fold increase in final purification yield over the parent. 相似文献
7.
Balaji Prakash S. Selvaraj M. R. N. Murthy Y. N. Sreerama D. Rajagopal Rao Lalitha R. Gowda 《Journal of molecular evolution》1996,42(5):560-569
Plant seeds contain a large number of protease inhibitors of animal, fungal, and bacterial origin. One of the well-studied
families of these inhibitors is the Bowman-Birk family(BBI). The BBIs from dicotyledonous seeds are 8K, double-headed proteins.
In contrast, the 8K inhibitors from monocotyledonous seeds are single headed. Monocots also have a 16K, double-headed inhibitor.
We have determined the primary structure of a Bowman-Birk inhibitor from a dicot, horsegram, by sequential edman analysis
of the intact protein and peptides derived from enzymatic and chemical cleavage. The 76-residue-long inhibitor is very similar
to that ofMacrotyloma axillare. An analysis of this inhibitor along with 26 other Bowman-Birk inhibitor domains (MW 8K) available in the SWISSPROT databank
revealed that the proteins from monocots and dicots belong to related but distinct families. Inhibitors from monocots show
larger variation in sequence. Sequence comparison shows that a crucial disulphide which connects the amino and carboxy termini
of the active site loop is lost in monocots. The loss of a reactive site in monocots seems to be correlated to this. However,
it appears that this disulphide is not absolutely essential for retention of inhibitory function. Our analysis suggests that
gene duplication leading to a 16K inhibitor in monocots has occurred, probably after the divergence of monocots and dicots,
and also after the loss of second reactive site in monocots.
S. Selvaraj is on leave from Department of Physics, Bharathidasan University, Tiruchirapalli 620 024, Tamilnadu, India
Correspondence to: M.R.N. Murthy 相似文献
8.
9.
Soybean Kunitz, C-II and PI-IV inhibitor genes confer different levels of insect resistance to tobacco and potato transgenic plants 总被引:1,自引:0,他引:1
S. Marchetti M. Delledonne C. Fogher C. Chiabà F. Chiesa F. Savazzini A. Giordano 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2000,101(4):519-526
In modern, highly intensive agriculture, the control of insect pests is basically achieved with the application of chemical
pesticides. Heavy reliance on this sole strategy is associated with several drawbacks, and the development of alternative
or complementary methods to chemical control is desirable. In this work, three soybean genes (KTi
3
, C-II and PI-IV)coding for serine proteinase inhibitors were isolated by PCR and transferred to Agrobacterium tumefaciens EHA 105, which in turn was used for transforming tobacco leaf and potato tuber discs. Biochemical assays confirmed that transgenic
plants synthesized serine proteinase inhibitors; rates of expression varied among plants. The level of insect resistance (tested
with Spodoptera littoralis Boisduval) was particularly high in tobacco, where many plants caused the death of all larvae. In potatoes, larval mortality
was much less frequently achieved, but the results were still encouraging in that larval weight gain was reduced by 50% in
the presence of adequate amounts of inhibitor. When 8-day-old larvae were fed different KTi
3
-expressing tobacco plants, a highly significant (P<0.01) correlation was observed between inhibitor content and larval live weight. Larval weight gain was found to be dependent
on midgut proteolytic activity. On the basis of the evidence collected, it is suggested that further work is required to identify
more specific inhibitors for the main proteinases of the target insect.
Received: 30 March 1998 / Accepted: 9 December 1999 相似文献
10.
Identification and characterization of a Bowman-Birk inhibitor active towards trypsin but not chymotrypsin in Lupinus albus seeds 总被引:1,自引:0,他引:1
Scarafoni A Consonni A Galbusera V Negri A Tedeschi G Rasmussen P Magni C Duranti M 《Phytochemistry》2008,69(9):1820-1825
The paper describes the purification, structural characterization and inhibitory properties of a trypsin inhibitor from Lupinus albus L., a leguminous plant believed to be devoid of any protease inhibitor. The protein has been isolated by a newly set-up procedure and characterized by direct amino acid sequencing, MALDI-TOF mass spectroscopy and circular dichroism. Inhibitory properties toward bovine trypsin and chymotrypsin, as well as its thermal and pH stabilities, have been also assessed. The inhibitor is 63 amino acid long (Mr 6858; pI 8.22) and it is capable to inhibit two trypsin molecules simultaneously, with a Kd of 4.2+/-0.4 nM, but not chymotrypsin. BLAST search against UniProtKB/TrEMBL database indicates that the inhibitor belongs to the Bowman-Birk inhibitor (BBI) family. The interest in these serine-protease inhibitors arises from the ability to prevent or suppress carcinogen-induced transformation, as shown in various in vitro and in vivo model systems. 相似文献