Isolation and characterization of the novel lipophilic protein, Pb CP-12.7, from the shell of the pink shrimp, Pandalus borealis.
(1/14)
Past research on diapause-inducing substances of the silkworm has isolated an extremely lipophilic peptide and demonstrated its unique characteristics. In the present work, similar lipophilic proteins were searched for in the shell of the shrimp, Pandalus borealis, and one novel protein, Pb CP-12.7, was isolated. Its structure comprising 126 amino acids was revealed by a combination of a sequence analysis and the enzymic fragmentation technique. Pb CP-12.7 is unique in that it was insoluble in neutral-slightly basic water, but highly soluble in some organic solvents. It contained an abundance of hydrophobic amino acids and repeating sequences. In addition, it was adsorbed to chitin, a major component of the shell of the shrimp. (+info)
Detection of cross-reactivity for atopic immunoglobulin E against multiple allergens.
(2/14)
The existence of specific immunoglobulin E (IgE) allows us to determine the allergens that cause the allergic disease. For the purposes of allergen avoidance and immunotherapy, the measurement of specific IgE is widely applied in clinical laboratories. However, if IgE from the serum of an allergic patient exhibits reactivity to multiple allergens, it would cause a problem. The present study analyzes whether the serum IgE with multiple reactivity is due to the presence of unique IgE against the common epitope shared by different allergens or the presence of multiple IgEs against different epitopes on different allergens. The quantitative-competitive inhibition tests and the immunoblotting were applied to analyze the immunosimilarity among examined allergens. The result shows that the competitive inhibition of IgE binding between shrimp and crab allergens is higher than those between either shrimp and cockroach or between crab and cockroach. Furthermore, the results of immunoblotting are consistent with those of quantitative-competitive inhibition tests. These results allow us to detect the cross-reactivity for atopic IgE against multiple allergens. (+info)
Molecular cloning and functional characterization of crustapain: a distinct cysteine proteinase with unique substrate specificity from northern shrimp Pandalus borealis.
(3/14)
A cDNA clone encoding a cysteine proteinase of the papain superfamily has been isolated from the hepatopancreas of northern shrimp Pandalus borealis (NsCys). NsCys shares the highest identity of 64% with a cathepsin L-like cysteine proteinase from lobster, and its identity to the well-characterized mammalian cathepsins S, L, and K falls within a narrow range of 54-59%. However, it differs from each of these cathepsins in certain key residues including, for example, the unique occurrence of tryptophan and cysteine residues at the structurally important S2 subsite. Consequently, NsCys produced in Pichia pastoris appears to be distinct in various physicokinetic properties. The recombinant enzyme is active and stable over a wide range of pH values, and its substrate specificity is unusual, as demonstrated by its poor affinity for phenylalanine residues. Instead, it shows the highest specificity for proline residues, a property similar to cathepsin K. Unlike cathepsin K, however, NsCys cleaves valine residues more efficiently than leucine. Similar results were obtained with the natural peptide substrate glucagon. The shrimp proteinase is further distinguished by its potent collagenolytic activity, resulting in a cleavage pattern reminiscent of bacterial collagenase. To distinguish such unique structural and enzymatic properties, we propose the trivial name "crustapain" for the shrimp proteinase, indicating that it is a papain-like cysteine proteinase from a crustacean species. (+info)
White spot syndrome virus open reading frame 222 encodes a viral E3 ligase and mediates degradation of a host tumor suppressor via ubiquitination.
(4/14)
We have characterized a white spot syndrome virus (WSSV) RING-H2-type protein, WSSV222, which is involved in ubiquitination. WSSV222 exhibits RING-H2-dependent E3 ligase activity in vitro in the presence of the specific conjugating enzyme UbcH6. Mutations in the RING-H2 domain abolished WSSV222-dependent ubiquitination, revealing the importance of this domain in WSSV222 function. Yeast two-hybrid and pull-down analyses revealed that WSSV222 interacts with a shrimp tumor suppressor-like protein (TSL) sharing 60% identity with human OVCA1. To better characterize the interaction of WSSV222 and TSL in vivo, we established a stable TSL-expressing cell line derived from the human ovarian cancer cell line A2780, where we observed a TSL-dependent prolonged G1 phase. Furthermore, we detected WSSV222-mediated ubiquitination and MG132-sensitive degradation of TSL both in shrimp primary cell culture and in the TSL-expressing cell line. Transient expression of TSL in BHK cells leads to apoptosis, which was rescued by WSSV222. Taken together, our data suggest that WSSV222 acts as an antiapoptosis protein by ubiquitin-mediated proteolysis of TSL to ensure successful WSSV replication in shrimp. (+info)
Prawns, barnacles, and nonsteroidal anti-inflammatory drugs: effect modifiers or diagnostic confounders [corrected].
(5/14)
A 42-year-old woman with no history of atopy reported several episodes of generalized urticaria and shortness of breath after eating shellfish (prawns and barnacles) but with good tolerance of the same foods between episodes. Skin prick tests (SPTs), serum enzyme allergosorbent tests (EAST) for specific immunoglobulin (Ig) E, Western blot and inhibition assays, and oral challenge tests with prawns, barnacles, nonsteroidal anti-inflammatory drugs (NSAIDs), and alcohol as potential effect modifiers were performed. Specific IgE to both barnacle and prawn were detected by SPTs and EAST. Results from a Western blot of raw prawn revealed an IgE binding band of 37 kDa and IgE binding bands of 143, 83, 38, 32, and 20 kDa appeared in the raw barnacle assay. Oral challenge tests were positive with prawns and prawn extract only if preceded by NSAIDs. Oral challenges with NSAIDs alone, prawns alone, barnacles with or without NSAIDs and alcohol led to no reaction. A synergistic effect of NSAIDs in inducing anaphylaxis after prawn intake was confirmed. No similar effect was achieved with barnacles despite the presence of specific IgE. Additional factors needed to elicit a clinical reaction in food allergy may not be obvious and several oral challenge protocols are mandatory in such cases. (+info)
Salinicoccus siamensis sp. nov., isolated from fermented shrimp paste in Thailand.
(6/14)
Fifteen strains of moderately halophilic, Gram-positive cocci were isolated from a traditional fermented shrimp paste ('ka-pi') produced in Thailand. These bacteria were strictly aerobic, non-motile, non-sporulating and catalase- and oxidase-positive. They produced orange pigment and grew in the presence of 1.5-25 % (w/v) NaCl. They grew optimally in 10 % (w/v) NaCl, at pH 8.5 and at 37 degrees C. The cell-wall peptidoglycan was of l-Lys type. Menaquinone with six isoprene units (MK-6) was a major component. The dominant cellular fatty acids were anteiso-C(15 : 0) and iso-C(15 : 0). DNA G+C contents were in the range 44.5-47.5 mol%. Comparative 16S rRNA gene sequence analyses indicated that representative strain PN1-2(T) was related most closely to Salinicoccus roseus JCM 14630(T), with 97.3 % similarity. The other novel strains were included in the same species based on their levels of DNA-DNA relatedness to strain PN1-2(T) (> or =76.6 %) but showed low DNA-DNA relatedness to S. roseus JCM 14630(T) (21.7 %). On the basis of the phenotypic and molecular data presented, the 15 novel strains are suggested to represent a single novel species of the genus Salinicoccus, for which the name Salinicoccus siamensis sp. nov. is proposed. The type strain is PN1-2(T) (=JCM 12822(T) =PCU 242(T) =TISTR 1562(T)). (+info)
Natronococcus jeotgali sp. nov., a halophilic archaeon isolated from shrimp jeotgal, a traditional fermented seafood from Korea.
(7/14)
A novel halophilic archaeon (strain B1(T)) belonging to the genus Natronococcus was isolated from shrimp jeotgal, a traditional fermented food from Korea. Colonies of this strain were orange-red and cells were non-motile cocci that stained Gram-variable. Strain B1(T) grew in 7.5-30.0 % (w/v) NaCl and at 21-50 degrees C and pH 7.0-9.5, with optimal growth occurring in 23-25 % (w/v) NaCl and at 37-45 degrees C and pH 7.5. Strain B1(T) was most closely related to the type strain of Natronococcus occultus, with which it shared 97.91 % 16S rRNA gene sequence similarity. Within the phylogenetic tree, this novel strain shared a branching point with N. occultus and occupied a phylogenetic position that was distinct from the main Natronococcus branch. The degree of DNA-DNA hybridization with the type strain of N. occultus, the most closely related species phylogenetically, was 16.4 %. On the basis of these results, it is concluded that strain B1(T) represents a novel species of the genus Natronococcus, for which the name Natronococcus jeotgali is proposed. The type strain is B1(T) (=KCTC 4018(T)=DSM 18795(T)=JCM 14583(T)=CECT 7216(T)). (+info)
Halalkalicoccus jeotgali sp. nov., a halophilic archaeon from shrimp jeotgal, a traditional Korean fermented seafood.
(8/14)
A novel, extremely halophilic archaeon B3(T) was isolated from shrimp-salted seafood. Its morphology, physiology, biochemical features and 16S rRNA gene sequence were characterized. Strain B3(T) is non-motile, Gram-variable, requires at least 10 % (w/v) NaCl for growth and grows in the ranges of 21-50 degrees C and pH 6.5-9.0. The DNA G+C content of strain B3(T) was 63.2 mol%. Phylogenetic analysis based on the 16S rRNA gene sequences indicated that strain B3(T) belonged to the genus Halalkalicoccus and was phylogenetically closely related to the type strain Halalkalicoccus tibetensis (98.64 %). However, DNA-DNA hybridization experiments showed 7.0 % relatedness between strain B3(T) and a strain of a reference species of the genus Halalkalicoccus. Combined analysis of 16S rRNA gene sequences, DNA-DNA relatedness data, physiological and biochemical tests indicated that the genotypic and phenotypic characteristics differentiate strain B3(T) from other Halalkalicoccus species. On the basis of the evidence presented in this report, strain B3(T) represents a novel species of the genus Halalkalicoccus, for which the name Halalkalicoccus jeotgali. sp. nov. is proposed. The type strain is B3(T) (=KCTC 4019(T)=DSM 18796(T)=JCM 14584(T)=CECT 7217(T)). (+info)