. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 670 K. SODERHALL ET AL. TABLE V Assays for phenoloxidase activity in Limulus hemolymph Phenoloxidase activity1 AA490 nm/60 min ml Treatment of Limulus amebocyte lysate (LAL) reaction mixture LAL 0 LAL + trypsin ( mg/ml) 0 LAL + CaCl2(10mAO 0 LAL + CaCl2 (10 mM) + trypsin ( mg/ml) 0 LAL + MgCl2 (50 mM) 0 LAL + MgG2 (50 mM) + trypsin ( mg/ml) 0 LAL + CaCl2 (10 mM) + MgCl2 (50 mM) + trypsin ( mg/ml) 0 Limulus plasma 0 Limulus plasma + trypsin 0 ' Enzyme activity determined as detailed in Materials and Methods. D
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 670 K. SODERHALL ET AL. TABLE V Assays for phenoloxidase activity in Limulus hemolymph Phenoloxidase activity1 AA490 nm/60 min ml Treatment of Limulus amebocyte lysate (LAL) reaction mixture LAL 0 LAL + trypsin ( mg/ml) 0 LAL + CaCl2(10mAO 0 LAL + CaCl2 (10 mM) + trypsin ( mg/ml) 0 LAL + MgCl2 (50 mM) 0 LAL + MgG2 (50 mM) + trypsin ( mg/ml) 0 LAL + CaCl2 (10 mM) + MgCl2 (50 mM) + trypsin ( mg/ml) 0 Limulus plasma 0 Limulus plasma + trypsin 0 ' Enzyme activity determined as detailed in Materials and Methods. DISCUSSION Limulus, like many large arthropods, is relatively long-lived, requiring 9-12 years to reach maturity (Shuster, 1950, 1954), and with a maximum lifespan estimated to be in excess of 14-19 years (Ropes, 1961). One requirement for such longevity is the ability to defend against potentially pathogenic microbes (for review see Armstrong, 1985). The cuticle and epidermis certainly form important barriers to penetration. The one well-studied internal defense mechanism in Limulus is activation of the clotting system by bacterial endotoxin (Bang, 1956, 1979; Shirodkar etai, 1960; Levin and Bang, 1964a, 1968; Levin, 1967; Stagner and Redmond, 1975). Other arthropods. FIGURE 3. Amebocyte tissue can be prepared for study by collecting blood under aseptic conditions in embryo watchglasses. After removal from the animal, the blood cells settle and aggregate into a tissue- like mass that, after an extended period in vitro, undergoes contraction. In right-hand watchglass, it is 1 day old. The amebocyte tissue mass has contracted into the compact, white, button-like mass in the upper left of the watchglass. Even at 1 or more days after preparation, the aggregated mass of blood cells is white in color, with no sign of melanization. The fluid medium was Limulus Please note that these images are extracted from scanned page images that may have been digitally enhanced for readab
Size: 2192px × 1140px
Photo credit: © Library Book Collection / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
