# PURIFICATION OF PROTEINS WITH BIOLOGICAL ACTIVITY

> **NIH NIH R01** · UNIVERSITY OF SOUTH DAKOTA · 1988 · $64,843

## Abstract

Ascaris lumbricoides, intestinal round worms, infect 23% of the world's
population.  Infestation is prominent in third world countries and it
compromises the nutrition available to its hosts because Ascaris are
parasites and may consume 200-300 calories per day.  The extent to which
they may be disease sectors transmitting viruses is still unknown.  Current
control is with chemical anthelmintics directed only at adult worms capable
of propagating themselves at the rate of hundreds of thousands per day.  So
long as the infected hosts live in an environment in which their food
sources and waste disposal are not separated, reinfestation is imminent and
chemical de-worming is of limited use.  We believe the protease inhibitors
in the parasite are critical to their survival, perhaps their species
specificity, and the most logical site to direct an attack at biologically
controlling their migration through their hosts.  This approach will
interrupt the life cycle of the parasite by preventing their development to
adults.  The approach is to examine each of the inhibitors from hog Ascaris
as pure chemicals:  isolate them, find their reactive sites, determine
their complete amino acid sequence and study their binding to host
proteases.  During this project period it will be possible to examine these
same compounds from Ascaris captured from humans to see if they contribute
to species specificity.

Studies to determine what role these inhibitors play in adults and
developing larvae are ongoing.  It was shown during this project period
that host proteins from the environment of the worm, trypsin and
chymotrypsin, enter adult worms and are also present inside of infective
(2nd stage) larvae.  Under natural conditions these larvae migrate through
the host and progress to third stage larvae in the lungs.  In the natural
host they are coughed up, swallowed, and some develop to adults.  In the
wrong host, the larvae do not complete their life cycle.  Sterling cultures
of lung stage larvae raised in their natural host will be established and
the role of stomach and pancreatic secretions containing natural
environmental proteins will be used to try to complete their life cycle and
determine which of the inhibitors might be the best candidate(s) for an
attack.

## Key facts

- **NIH application ID:** 3124888
- **Project number:** 5R01AI010992-17
- **Recipient organization:** UNIVERSITY OF SOUTH DAKOTA
- **SAM.gov UEI:** U9EDNSCHTBE7
- **Principal Investigator:** ROBERT J PEANASKY
- **Activity code:** R01 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 1988
- **Award amount:** $64,843
- **Award type:** 5
- **Project period:** 1979-04-01 → 1990-06-30

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/3124888

## Citation

> US National Institutes of Health, RePORTER application 3124888, PURIFICATION OF PROTEINS WITH BIOLOGICAL ACTIVITY (5R01AI010992-17). Retrieved via MORVS 2026-10-25 from https://api.morvs.ai/grant/nih/3124888. Licensed CC0.

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