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PubMed · 6714430

Differences in polypeptide composition and enzyme activity between cold-stable and cold-labile microtubules and study of microtubule alkaline phosphatase activity.

J E Hesketh
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Abstract

Cold-stable and cold-labile microtubules were prepared by two cycles of assembly and disassembly and two periods of exposure to cold. The cold-labile preparations were shown to contain a higher proportion of a high molecular mass microtubule-associated protein (MAP 2) than cold-stable preparations. The cold-stable preparations showed a much higher alkaline phosphatase activity. Stimulation of microtubule assembly by zinc led to increases in both cold stability and alkaline phosphatase activity.

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Alkaline PhosphataseAnimalsBrainCold TemperatureIn Vitro TechniquesMagnesiumMaleMicroscopy, ElectronMicrotubule-Associated ProteinsMicrotubulesMolecular WeightProteinsRatsZincJournal Article

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J E Hesketh. 1984-04-24. Differences in polypeptide composition and enzyme activity between cold-stable and cold-labile microtubules and study of microtubule alkaline phosphatase activity.. https://doi.org/10.1016/0014-5793(84)80341-5

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Alkaline Phosphatase↗
PubMed1996

A potential use of a monoclonal antibody to placental alkaline phosphatase (PLAP) to detect lymph node metastases of seminoma.

PURPOSE: To evaluate the ability of monoclonal antibodies against alkaline phosphatase (AL-P) for tumor immunolocalization in nude mice. MATERIALS AND METHODS: Two monoclonal antibodies against placental alkaline phosphatase (PLAP) and liver alkaline phosphatase (LAP) were intravenously administered to nude mice bearing AL-P producing HeLa Hep 2 tumors. Sera and tumors from 65 patients with testicular germ cell tumors were examined for PLAP levels. RESULTS: Levels of PLAP or LAP in the HeLa xenografts were shown to be comparable to levels of PLAP in seminomas, including lymph node metastases, or nonseminomas, respectively. A biodistribution study showed that the percentage of the injected dose of I-125 labelled anti-PLAP in the xenografts was rather constant at around 7% until 7 days after injection, while the percentage of the injected dose of I-125 labelled anti-LAP MAb decreased with time as in other tissues which do not contain significant amounts of PLAP or LAP. On scintiscan, the xenografts in nude mice were distinctly visualized at 7 days after injection of anti-PLAP MAb. CONCLUSIONS: These data may support the potential use of the anti-PLAP MAb for the immunodetection of lymph node metastases of seminoma.

Alkaline Phosphatase↗
PubMed1995

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Structurally intact and functionally active human bone alkaline phosphatase was isolated from clavicle fragments of IDU, an Egyptian mummy of the Old Kingdom (2150 +/- 50 BC). Both anion exchange and affinity chromatographies were employed to optimise the preparation of the ancient enzyme resulting in a specific activity of 180 +/- 30 mU/mg. The intactness of the bone enzyme fractions of the wheat-germ lectin affinity chromatography was successfully demonstrated in an ELISA using the monoclonal antibody BAP A. Fortunately, the mummified bone was not contaminated by fungi or bacteria.

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