Bacillus thuringiensis var. israelensis δ-endotoxin

Evidence of neurotoxic action

Peter Y K Cheung, Dan Buster, Bruce D. Hammock, R. Michael Roe, A. Randall Alford

Research output: Contribution to journalArticle

4 Citations (Scopus)

Abstract

The neurotoxic, cytolytic, and lethal properties of a 25-kDa protein isolated from the δ-endotoxin of Bacillus thuringiensis subsp. israelensis (Bti) were compared with those of the alkaline-dissolved whole extract of the δ-endotoxin and the cytolytic enzyme phospholipase A2. In situ electrophysiological measurements of the ventral nerve cord of larval Trichoplusia ni treated at 15 and 25°C with various dosages of the three protein preparations showed that only the whole extract of the δ-endotoxin induced hyperexcitation. When the appearance of lactate dehydrogenase activity in the haemolymph of toxin-injected larvae was used to quantitate cell lysis, the cytolytic 25-kDa protein was found to be a potent cytotoxic factor like phospholipase A2, whereas cytotoxicity of the whole δ-endotoxin extract was relatively low. Bioassays at 28, 17, and 9°C demonstrated a positive temperature correlation with mortality for the whole toxin extract, but showed inverse correlations for the two cytolytic materials. This and previous studies indicate that insect mortality is not solely due to the cytolytic activity of the Bti δ-endotoxin upon injection into T. ni. An unidentified neurotoxic factor(s) exists within the Bti δ-endotoxin which induces hyperexcited activity in the insect nervous system. This and/or other factors impart the δ-endotoxin with biological and physiological activities different from the isolated cytolytic component.

Original languageEnglish (US)
Pages (from-to)42-49
Number of pages8
JournalPesticide Biochemistry and Physiology
Volume27
Issue number1
DOIs
StatePublished - 1987

Fingerprint

Bacillus thuringiensis subsp. israelensis
Bacillus thuringiensis
Bacilli
endotoxins
Endotoxins
Trichoplusia ni
phospholipase A2
Phospholipases A2
extracts
Insects
toxins
ventral nerve cord
insects
Proteins
proteins
Hemolymph
Mortality
Bioassay
Neurology
Cytotoxicity

ASJC Scopus subject areas

  • Agronomy and Crop Science
  • Biochemistry
  • Physiology

Cite this

Bacillus thuringiensis var. israelensis δ-endotoxin : Evidence of neurotoxic action. / Cheung, Peter Y K; Buster, Dan; Hammock, Bruce D.; Roe, R. Michael; Alford, A. Randall.

In: Pesticide Biochemistry and Physiology, Vol. 27, No. 1, 1987, p. 42-49.

Research output: Contribution to journalArticle

Cheung, Peter Y K ; Buster, Dan ; Hammock, Bruce D. ; Roe, R. Michael ; Alford, A. Randall. / Bacillus thuringiensis var. israelensis δ-endotoxin : Evidence of neurotoxic action. In: Pesticide Biochemistry and Physiology. 1987 ; Vol. 27, No. 1. pp. 42-49.
@article{c46c265652b14f8eae476082d8ed9cd9,
title = "Bacillus thuringiensis var. israelensis δ-endotoxin: Evidence of neurotoxic action",
abstract = "The neurotoxic, cytolytic, and lethal properties of a 25-kDa protein isolated from the δ-endotoxin of Bacillus thuringiensis subsp. israelensis (Bti) were compared with those of the alkaline-dissolved whole extract of the δ-endotoxin and the cytolytic enzyme phospholipase A2. In situ electrophysiological measurements of the ventral nerve cord of larval Trichoplusia ni treated at 15 and 25°C with various dosages of the three protein preparations showed that only the whole extract of the δ-endotoxin induced hyperexcitation. When the appearance of lactate dehydrogenase activity in the haemolymph of toxin-injected larvae was used to quantitate cell lysis, the cytolytic 25-kDa protein was found to be a potent cytotoxic factor like phospholipase A2, whereas cytotoxicity of the whole δ-endotoxin extract was relatively low. Bioassays at 28, 17, and 9°C demonstrated a positive temperature correlation with mortality for the whole toxin extract, but showed inverse correlations for the two cytolytic materials. This and previous studies indicate that insect mortality is not solely due to the cytolytic activity of the Bti δ-endotoxin upon injection into T. ni. An unidentified neurotoxic factor(s) exists within the Bti δ-endotoxin which induces hyperexcited activity in the insect nervous system. This and/or other factors impart the δ-endotoxin with biological and physiological activities different from the isolated cytolytic component.",
author = "Cheung, {Peter Y K} and Dan Buster and Hammock, {Bruce D.} and Roe, {R. Michael} and Alford, {A. Randall}",
year = "1987",
doi = "10.1016/0048-3575(87)90094-0",
language = "English (US)",
volume = "27",
pages = "42--49",
journal = "Pesticide Biochemistry and Physiology",
issn = "0048-3575",
publisher = "Academic Press Inc.",
number = "1",

}

TY - JOUR

T1 - Bacillus thuringiensis var. israelensis δ-endotoxin

T2 - Evidence of neurotoxic action

AU - Cheung, Peter Y K

AU - Buster, Dan

AU - Hammock, Bruce D.

AU - Roe, R. Michael

AU - Alford, A. Randall

PY - 1987

Y1 - 1987

N2 - The neurotoxic, cytolytic, and lethal properties of a 25-kDa protein isolated from the δ-endotoxin of Bacillus thuringiensis subsp. israelensis (Bti) were compared with those of the alkaline-dissolved whole extract of the δ-endotoxin and the cytolytic enzyme phospholipase A2. In situ electrophysiological measurements of the ventral nerve cord of larval Trichoplusia ni treated at 15 and 25°C with various dosages of the three protein preparations showed that only the whole extract of the δ-endotoxin induced hyperexcitation. When the appearance of lactate dehydrogenase activity in the haemolymph of toxin-injected larvae was used to quantitate cell lysis, the cytolytic 25-kDa protein was found to be a potent cytotoxic factor like phospholipase A2, whereas cytotoxicity of the whole δ-endotoxin extract was relatively low. Bioassays at 28, 17, and 9°C demonstrated a positive temperature correlation with mortality for the whole toxin extract, but showed inverse correlations for the two cytolytic materials. This and previous studies indicate that insect mortality is not solely due to the cytolytic activity of the Bti δ-endotoxin upon injection into T. ni. An unidentified neurotoxic factor(s) exists within the Bti δ-endotoxin which induces hyperexcited activity in the insect nervous system. This and/or other factors impart the δ-endotoxin with biological and physiological activities different from the isolated cytolytic component.

AB - The neurotoxic, cytolytic, and lethal properties of a 25-kDa protein isolated from the δ-endotoxin of Bacillus thuringiensis subsp. israelensis (Bti) were compared with those of the alkaline-dissolved whole extract of the δ-endotoxin and the cytolytic enzyme phospholipase A2. In situ electrophysiological measurements of the ventral nerve cord of larval Trichoplusia ni treated at 15 and 25°C with various dosages of the three protein preparations showed that only the whole extract of the δ-endotoxin induced hyperexcitation. When the appearance of lactate dehydrogenase activity in the haemolymph of toxin-injected larvae was used to quantitate cell lysis, the cytolytic 25-kDa protein was found to be a potent cytotoxic factor like phospholipase A2, whereas cytotoxicity of the whole δ-endotoxin extract was relatively low. Bioassays at 28, 17, and 9°C demonstrated a positive temperature correlation with mortality for the whole toxin extract, but showed inverse correlations for the two cytolytic materials. This and previous studies indicate that insect mortality is not solely due to the cytolytic activity of the Bti δ-endotoxin upon injection into T. ni. An unidentified neurotoxic factor(s) exists within the Bti δ-endotoxin which induces hyperexcited activity in the insect nervous system. This and/or other factors impart the δ-endotoxin with biological and physiological activities different from the isolated cytolytic component.

UR - http://www.scopus.com/inward/record.url?scp=0023081621&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0023081621&partnerID=8YFLogxK

U2 - 10.1016/0048-3575(87)90094-0

DO - 10.1016/0048-3575(87)90094-0

M3 - Article

VL - 27

SP - 42

EP - 49

JO - Pesticide Biochemistry and Physiology

JF - Pesticide Biochemistry and Physiology

SN - 0048-3575

IS - 1

ER -