ISSN:0739-4462    

DOI:10.1002/arch.940170102

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1991

数据来源: WILEY

摘要:

AbstractKc‐cells fromDrosophila melanogaster, grown under serum‐free conditions, produce two β‐hexosaminidases and secrete these enzymes into the medium. The two enzymes were separated by DEAE‐exchange chromatography. According to their substrate specificities one enzyme is a β‐N‐acetyl‐D‐glucosaminidase (E.C.3.2.1.30), the other one a β‐N‐acetyl‐D‐hexosaminidase (E.C.3.2.1.52). The β‐N‐acetyl‐D‐glucosaminidase is predominant in the medium, the β‐N‐acetyl‐D‐hexosaminidase within the cells. The Kmvalues for the substrates pNP‐GlcNAc, pNP‐GalNAc, and (GlcNAc)2are 0.8, 16.73, and 1.67 mM for the β‐N‐acetyl‐D‐glucosaminidase and 0.24, 0.44, and 0.2 mM for the β‐N‐acetyl‐D‐hexosaminidase. Both enzymes are inhibited by the products and the β‐N‐acetyl‐D‐glucosaminidase is also inhibited stereospecifically by the substrates pNP‐GlcNAc and (GlcNAc)2. Both enzymes are inhibited in a

ISSN:0739-4462    

DOI:10.1002/arch.940170103

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1991

数据来源: WILEY

摘要:

AbstractA larval specific high‐density lipoprotein (HDL) has been isolated fromMusca domesticahemolymph by a combination of density gradient and glycerol gradient ultracentrifugations. The larval lipoprotein has a density of 1.134 g/ml and is formed by at least four apoproteins with molecular weights equal to 26,000, 23,000, 21,000, and 20,000. This lipoprotein contains large amounts of hydrocarbons and phospholipids and minor amounts of diacylglycerols and cholesterol. The larval lipoprotein is completely distinct from lipophorin in regard to apoprotein composition, lipid moiety, physiological pattern, and immunological reactions. Larval lipoprotein is accumulated until the end of the feeding period. During the pupal molt this protein is utilized and is no longer detected after 2 days of pupal stadium. The results obtained imply a possible role of this protein in the puparia and/or pupal cuticle formation. Judging from the properties shown, theMusca domesticalarval lipoprotein is a completely new type of insect lipoprotei

ISSN:0739-4462    

DOI:10.1002/arch.940170104

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1991

数据来源: WILEY

摘要:

AbstractIn this study the flight activity of female and maleHelicoverpa zea(Boddie) moths was observed and compared to hemolymph lipid concentrations. The major male and femaleH. zeaflight activity occurred between simulated dusk (1700) and dawn (0300). Male flight activity was up to 7 times greater than females through 6 days after eclosion except for the 1st day (0.8 times). Females had a unimodal pattern of flight activity, peaking between dusk and 2 h later. Males had a bimodal pattern; one between dusk and 2 h later, and another 3 h after dusk, continuing for h. Prior to dusk, total neutral hemolymph lipids (neutral) ofH. zeaday 4 moths was 64 μg/μl for males and 48 μg/μl for females. Typical lipid composition in day 4 males prior to flight was 1,2‐diacylglycerides (DG) (50% w/w), triacylglycerides (TG) (35%), cholesterol esters (2%), and less than 1% monoacylglycerides and cholesterol. The remainder consisted of free fatty acids (<0.5 μg/μl), and various uncharacterized phospholipids and lipophilic compounds. Hemolymph DG concentration patterns were similar between day 4 males and females, were highest in both sexes prior to, during, and after flight (approximately 32 μg/μl), and then decreased steadily throughout the flight period to approximately 16 μg/ml as flight ceased. Hemolymph TG were lower than DG, but followed the same pattern except at 2100 and 2300. In day 4 males between 2100 and 2300, TG increased to 33 μg/μl which was when DG was lowest (15 μg/μl) and their flight activity was highest. Hemolymph DG decreased (26 to 20 μg/μl) in day 4 females between 2100 and 2300 as TG remained fairly con

ISSN:0739-4462    

DOI:10.1002/arch.940170105

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1991

数据来源: WILEY

摘要:

AbstractTo identify the tissues which produce hemolymph lectin in larvae ofBombyx mori, ovary, testis, fat body, and hemocytes from 5th‐instar larvae were cultured in vitro and the culture medium was partially purified and assayed for hemagglutinating activity. Among the tissues tested, hemocytes appeared to be a major source of the hemolymph lectins. Ovary produced lectins to about one‐tenth of the amount observed for the hemocytes, whereas testis and fat body were not productive. To study the hormonal control of hemolymph lectin production by hemocytes, hemocytes from 4th‐instar larvae were cultured in vitro. Hemagglutinating activity in the hemolymph of 4th‐instar larvae was immunostainable with the monoclonal antibody raised against 350,000 dalton lectin found in the 5th‐instar hemolymph, but their molecular sizes were larger than the 5th‐instar hemolymph lectins. When 20‐hydroxyecdysone was added into the medium, production of the lectin by the hemocytes was remarkably enhanced, depending upon the hormone

ISSN:0739-4462    

DOI:10.1002/arch.940170106

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1991

数据来源: WILEY

摘要:

AbstractThe fat body ofChortoicetes terminifera(Walker) (Orthoptera: Acrididae) parasitized byTrichopsidea oestracea(Westwood) (Diptera: Nemestrinidae) was hypertrophied and showed extensive cytological and functional changes. Lipid content (as a percentage of dry weight) was significantly higher in parasitized locusts. Regression of lipid content against parasitoid weight was quadratic in female hosts and linear (negative) in male hosts. The fatty acid composition ofC. terminiferawas not affected by parasitization. Parasitized male locusts had lower body weight than nonparasitized males and contained less soluble protein. Results indicated that egg development was inhibited in parasitized female locusts. These conditions may be related to changes in the host's fat body.

ISSN:0739-4462    

DOI:10.1002/arch.940170107

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1991

数据来源: WILEY

ISSN:0739-4462    

DOI:10.1002/arch.940170108

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1991

数据来源: WILEY

ISSN:0739-4462    

DOI:10.1002/arch.940170101

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1991

数据来源: WILEY