Acid phosphatases of Metarhizium anisopliae during infection of the tobacco hornworm Manduca sexta
Acid phosphatases of Metarhizium anisopliae during infection of the tobacco hornworm Manduca sexta
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DOI：
10.1007/s002030100342
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发表时间：
2001-09
影响因子：
2.8
通讯作者：
Yuxian Xia;J. Clarkson;K. Charnley
中科院分区：
文献类型：
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作者：
Yuxian Xia;J. Clarkson;K. Charnley
从昆虫病原真菌绿僵菌的优化培养物中分离、纯化和部分鉴定了3种酸性磷酸酶(ACP)同工酶，pI分别为8.1、8.0和7.8。这两种酶具有相似的分子质量(约44.0 kDa)，可以降解寄主昆虫烟草天牛的血淋巴中发现的糖磷酸盐。真菌感染昆虫血淋巴中ACP活性显著高于对照，并出现了一些新的同工酶。感染相关的亚型在分子质量和等电点上与一些体外ACP同工酶相似。金黄色葡萄球菌。斑点印迹和抗ACP抗体的Western印迹分析结果表明，在感染的毛虫血淋巴中至少存在一种变态磷酸酶。抗体不与免疫的(化学刺激的)或非免疫的六钩藻血淋巴发生交叉反应。与毛虫血液中高活性真菌磷酸酶的出现相一致，在感染的后期，游离磷浓度急剧增加，达到对照组的2-5倍。在对照血淋巴中磷的浓度限制了真菌的生长，添加磷显着促进了血淋巴中真菌的体外生长。这些结果表明，绿僵菌AcP可能在以牺牲昆虫为代价为真菌生长提供磷的过程中发挥关键作用。
Three acid phosphatase (AcP) isozymes, pI 8.1, 8.0 and 7.8, were isolated, purified and partially characterised from optimised cultures of the entomopathogenic fungusMetarhizium anisopliae. The enzymes had similar molecular masses (approximately 44.0 kDa), and could degrade sugar phosphates found in the haemolymph of a host insect, the tobacco hornwormManduca sexta. The AcP activity in haemolymph of mycosed insects increased significantly over controls, and some new isozymes were present. The infection-related isoforms were similar in molecular mass and pI to some of the in vitro AcP isozymes ofM. anisopliae. Results of dot blot and Western blot analyses using anti-AcP antibodies suggested that at least oneMetarhiziumphosphatase isoform was present in haemolymph of infected caterpillars. Antibodies did not cross-react with immune (chemically stimulated) or non-immune haemolymph fromManduca sexta. Consistent with the appearance of highly active fungal phosphatase in caterpillar blood, free phosphate concentration increased dramatically during the late stages of infection to a level two to five times that of controls. Phosphate was limiting to growth of the fungus at the concentration found in control haemolymph and supplementation of phosphate significantly increased fungal growth in vitro in haemolymph. These results suggest thatMetarhiziumAcP may play a key role in providing phosphorus for fungal growth at the expense of the insect.