Parallel motor pathways from thoracic interneurons of the ventral giant interneurons system of the cockroach,Periplaneta americana

1990 ◽  
Vol 21 (8) ◽  
pp. 1219-1235 ◽  
Author(s):  
Roy E. Ritzmann ◽  
Alan J. Pollack
Keyword(s):  
Periplaneta Americana ◽  
Motor Pathways ◽  
Giant Interneurons

Activation of DUM cell interneurons by ventral giant interneurons in the cockroach,periplaneta americana

1988 ◽  
Vol 19 (6) ◽  
pp. 489-497 ◽  
Author(s):  
Alan J. Pollack ◽  
Roy E. Ritzmann ◽  
Joanne Westin
Keyword(s):  
Periplaneta Americana ◽  
Giant Interneurons

PENELITIAN EKSTRAKSI DAN KARAKTERISASI AGGREGATION PHEROMONE DARI KECOA (Periplaneta americana L)

2008 ◽  
pp. 8-13
Author(s):  
Sri Pudji Rahayu
Keyword(s):  
Aggregation Pheromone ◽  
Periplaneta Americana

Kecoa merupakan serangga yang suka hidup ditempat terlindung, tertutup maupun lipatan-lipatan sehingga susah diberantas, akan tetapi serangga tersebut mempunyai alat komunikasi yang  digunakan untuk memanggil sesamanya untuk berkumpul yang disebut aggregation pheromone. Aggregation pheromone ini diteliti untuk dimanfaatkan sebagai salah satu cara pengendaliannya. Pada penelitian ini aggregation pheromone diteliti dengan mengekstrak kotoran kecoa dengan berbagai macam pelarut dan hasil ekstraknya diuji secara biologi ditunjukkan dengan banyaknya kecoa yang datang dan berkumpul pada ekstrak AP tersebut. Dalam penelitian ini pelarut methanol merupakan pelarut yang paling baik dalam ekstraksi AP yang ditunjukkan adanya 80% kecoa yang datang berkumpul. Dari ekstraksi tersebut setelah dianalisa dengan alat kromatografi gas diperoleh senyawa aktif yang merupakan Aggregation pheromone dari kecoa Periplaneta americana L.  Senyawa tersebut diduga periplanon A dan periplanon B dengan waktu retensi 25,417 menit dan senyawa B dengan waktu retensi 27,007 menit.

Glycogen Phosphorylase in the Fat Body of Two Cockroach Species, Periplaneta americana and Nauphoeta cinerea: Isolation, Partial Characterization of Three Forms and Activation by Hypertrehalosaemic Hormones

1991 ◽  
Vol 46 (1-2) ◽  
pp. 149-162 ◽  
Author(s):  
Gerd Gäde
Keyword(s):  
Anion Exchange ◽  
Glycogen Phosphorylase ◽  
Periplaneta Americana ◽  
Fat Body ◽  
Phosphorylase Kinase ◽  
Phosphorylase Activity ◽  
Strong Inhibitor ◽  
Nauphoeta Cinerea ◽  
Crude Extracts ◽  
Fat Bodies

The presence of endogenous phosphorylase kinase and phosphorylase phosphatase in crude extracts of fat bodies from the cockroaches Nauphoeta cinerea and Periplaneta americana is demonstrated in vitro by activation/inactivation of glycogen phosphorylase under appropriate conditions. Fractionation of fat body extracts of both cockroach species on an anion-exchange medium results in the elution of three peaks with phosphorylase activity. According to their AMP dependency these activity peaks are designated as phosphorylase b (inactive without AMP), phosphorylase ab (active without AMP, but several stimulated with AMP) and phosphorylase a (active without AMP). It is shown chromatographically that incubating crude extracts of fat bodies from both cockroaches, under conditions where the phosphorylase kinase is active, results in all phosphorylase b being converted to the ab- or a-form , whereas under conditions where the phosphorylase phosphatase is active all phophorylase a is converted to the ab- or b-form . Endogenous phosphorylase kinase of N. cinerea crude fat body extract can convert vertebrate phosphorylase b into the a-form , and, conversely, vertebrate muscle p hosphorylase kinase and phosphorylase phosphatase, respectively, are able to convert partially purified N. cinerea phosphorylase aborb and the ab- und a-form , respectively. In resting cockroaches most of the phosphorylase activity resides in the b-form and only a small fraction (10% ) in the a-form , whereas between 26% (N . cinerea) and 35% (P. americana) occurs in the ab-form . Injection of endogenous hypertrehalosaemic peptides into N. cinerea (the decapeptide Bld-HrTH ) or P. americana (the two octapeptides Pea-CAH -I and II) causes interconversion of phosphorylase; after injection, mainly (60% ) phosphorylase a is present, while 25% and 15% exists in the ab- und b-form , respectively. Purification of the three phosphorylase forms from N. cinerea is achieved by anion-exchange chromatography on DEAE-Sephacel followed by affinity chromatography on AMP-Sepharose. The final specific activities are 2.1, 6.9 and 27.2 U /mg protein for the a-, ab- und b-form . The molecular mass of the active molecules on gel filtration is between 173,000 and 177,000, and SDS gel electrophoresis reveals a subunit mass of 87,100, suggesting a homodimeric structure for all three form s. Kinetic studies show hyperbolic saturation curves for the substrates glycogen and Pi respectively, with Kᴍ-values of 0.021, 0.019 and 0.073% for glycogen and 8.3, 6.3 and 17.9 mᴍ for Pi (a-, ab- and b-form ). Phosphorylase a exhibits a more or less hyperbolic response to AMP and needs 70 |iM A M P for m axim al stim ulation. The kinetics for the ab- and b-form s are sigm oidal and maximal activities are displayed at about 3 mᴍ (half-maximum activation as calculated from Hill plots are 55 and 280 μᴍ for the ab- und b-form , respectively). Caffeine is a strong inhibitor of the b-form , but has only a slight inhibiting effect (10 -20 % ) on the ab- and a-form in the presence of AMP.

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