GMW: GM cows for GM drugs/Briefing on GM animal feeds

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GMW: GM cows for GM drugs/Briefing on GM animal feeds

" GM WATCH " <info

Fri, 26 May 2006 11:25:54 +0100

 

 

 

 

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http://www.gmwatch.org

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Briefing on GM animal feeds

 

Friends of the Earth have updated their briefing on GM animal feeds:

http://www.foe.co.uk/resource/briefings/gm_animal_feeds.pdf

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GM cows for GM drugs

 

Mastitis is a nasty disease of the mammary gland to which cows in

indutrial agriculture are particularly prone.

 

Mastitis is said to cost the U.S. dairy industry approximately $2

billion annually - and the problem is made considerably worse by

Monsanto's

genetically engineered cattle drug, aimed at boosting milk production,

rBGH (also knowwn as BST and commercially 'Prosilac'). For this reason

Monsanto's GM drug is banned in Europe not only on human health grounds

but on animal welfare grounds as well. The GM cattle drug is also

banned on animal welfare grounds in Canada.

 

But never fear, a U.S. Agricultural Research Service (ARS)-led team are

developing transgenic dairy cows that are enginneered to have a

built-in defense against mastitis. This, of course, means it will be

easier to

give these cows a GM hormone to give more milk...

 

Below are several items relating to this exciting technological

breakthrough, including comment from the geneticist Prof Joe Cummins who

thinks kids who drink the resulting milk may suffer injury or death from

allergy.

 

But, hey, when you're talking 2 billion a year and increased profits

for Monsanto...

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Prof Joe Cummins:

 

Recently there has been publicity on USDA's introduction of cows with

synthetic genes. Essentially the synthetic genes are made up an

antibacterial gene from Staphylococcus (lyphostatin) joined to a gene

from a

Streptococcus bacteria phage specifying endolysin that dissolves

bacteria. The genes are altered in DNA sequence and truncated. The

synthetic

gene is used to modify cows so they produce milk that kills bacteria. One

problem discussed was allergy of the milk protein. It was pointed out

that the cows bearing the synthetic gene were unlikely to be allergic to

the toxin because it is a part of their genome thus recognized as self.

They failed to mention that kids drink the allergenic milk and do not

recognize it as self. Efforts were made to alter the DNA sequences

specify sugar additions to the protein to avoid human allergy (allergy

sites

on proteins are often have signals for sugar added to the protein) but

that approach was only partly effective.

 

The problem I see is that USDA regulates the things that they own

patents for the cows with synthetic genes which are likely to cause a

lot

of injury to people if they are rushed to commerce. However, USDA’s

synthetic genes may solve one of Monsanto's greatest problems with its

growth hormone, that is the good news, the bad news is that kids who

drink the milk may suffer injury or death from allergy.

 

Transgenic Research

Publisher: Springer Netherlands

ISSN: 0962-8819 (Paper) 1573-9368

DOI: 10.1007/s11248-005-0670-8

Issue: Volume 14, Number 5

 

October 2005

Pages: 563 - 567

Perspective

Engineering Disease Resistant Cattle

David M. Donovan1, David E. Kerr2 and Robert J. Wall1

 

Abstract: Mastitis is a disease of the mammary gland caused by

pathogens that find their way into the lumen of the gland through the

teat

canal. Mammary gland infections cost the US dairy industry

approximately $2

billion dollars annually and have a similar impact in Europe. In the

absence of effective treatments or breeding strategies to enhance

mastitis resistance, we have created transgenic dairy cows that express

lysostaphin in their mammary epithelium and secrete the antimicrobial

peptide

into milk. Staphylococcus aureus, a major mastitis pathogen, is

exquisitely sensitive to lysostaphin. The transgenic cattle resist S.

aureus

mammary gland challenges, and their milk kills the bacteria, in a dose

dependent manner. This first step in protecting cattle against mastitis

will be followed by introduction of other genes to deal with potential

resistance issues and other mastitis causing organisms. Care will be

taken to avoid altering milk’s nutritional and manufacturing

properties. Multi-cistronic constructs may be required to achieve our

goals as

will other strategies possibly involving RNAi and gene targeting

technology. This work demonstrates the possibility of using transgenic

technology to address disease problems in agriculturally important

species.

 

Applied and Environmental Microbiology, April 2006, p. 2988-2996, Vol

72, No. 4

doi:10.1128/AEM.72.4.2988-2996.2006

Peptidoglycan Hydrolase Fusions Maintain Their Parental Specificities

David M. Donovan,1* Shengli Dong,2 Wes Garrett,1 Geneviève M.

Rousseau,3

Sylvain Moineau,3 and David G. Pritchard2

 

The increased incidence of bacterial antibiotic resistance has led to a

renewed search for novel antimicrobials. Avoiding the use of

broad-range antimicrobials through the use of specific peptidoglycan

hydrolases

(endolysins) might reduce the incidence of antibiotic-resistant

pathogens worldwide. Staphylococcus aureus and Streptococcus

agalactiae are

human pathogens and also cause mastitis in dairy cattle. The ultimate

goal

of this work is to create transgenic cattle that are resistant to

mastitis through the expression of an antimicrobial protein(s) in their

milk. Toward this end, two novel antimicrobials were produced. The (i)

full-length and (ii) 182-amino-acid, C-terminally truncated S. agalactiae

bacteriophage B30 endolysins were fused to the mature lysostaphin

protein of Staphylococcus simulans. Both fusions display lytic

specificity

for streptococcal pathogens and S. aureus. The full lytic ability of the

truncated B30 protein also suggests that the SH3b domain at the C

terminus is dispensable. The fusions are active in a milk-like

environment.

They are also active against some lactic acid bacteria used to make

cheese and yogurt, but their lytic activity is destroyed by

pasteurization

(63°C for 30 min). Immunohistochemical studies indicated that the

fusion proteins can be expressed in cultured mammalian cells with no

obvious deleterious effects on the cells, making it a strong candidate

for

use in future transgenic mice and cattle. Since the fusion peptidoglycan

hydrolase also kills multiple human pathogens, it also may prove useful

as a highly selective, multipathogen-targeting antimicrobial agent that

could potentially reduce the use of broad-range antibiotics in fighting

clinical infections.

y

 

 

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