Team:Tec-Chihuahua/Description

Erwinions

Abstract

American and European Foulbrood are diseases that affect bee (Apis mellifera) larvae worldwide. In the last two years, 53 countries suffered from these diseases, 6 of them are among the top 10 honey producers. The causal agents of these ailments are gram-positive bacteria: Paenibacillus larvae and Melissococcus plutonius respectively. Nowadays, two techniques for the treatment of Foulbrood are used: antibiotics and incineration of hives. The former promotes the development of antibiotic resistance in bacteria while the latter results unprofitable for beekeepers. Therefore, we propose the production of bee antimicrobial peptides (AMPs) in Escherichia coli to treat P. larvae and M. plutonius infections. Defensin 1, abaecin, defensin 2, and apidaecin are each expressed in a different BL21 (DE3) culture. PelB leader peptide and a 6X His-tag foster adequate expression and further purification. Through mathematical modeling, the diffusivity of PLGA-nanoencapsulated apidaecin is evaluated for future in vivo delivery in the bee system.

Introduction

The most significant agricultural management practice is, without a doubt, pollination. Crops that directly rely on this activity are estimated to have a global price tag of between US$235 and US$577 billion a year. In fact, 87% of the food we consume depends on pollination.¹ Apis mellifera ranks as the most frequent species of pollinator for crops worldwide ² making possible and is responsible for the production of strawberry, alfalfa, avocado, coffee, apples, lemons, among many others.³ Bees improve the food production of 2 billion small farmers around the world helping guarantee the food security of the world population.⁴

Pollination is the greatest strength of bees, but that's not all they do; the world honey market reported historical highs during 2015, with volumes of operations exceeding 2,300 million dollars. In 2016, Mexico contributed 55,358 tons to the world market, with a value of 2,279 million Mexican pesos. ⁵ Beekeeping in Mexico has great socio-economic importance since it is considered as one of the main livestock activities generating foreign income ⁶, emphasizing that the third part of Mexico’s agricultural production depends on bees. ⁷

Figure 1: Not properly pollinated cucumber, promoting a poor development

Yet in the midst of the highly demanded bee population, beekeepers of multiple continents have suffered severe colony losses in recent years and this issue is ascribed to Colony Collapse Disorder, that corresponds to the 30% annual lost in the number of hives worldwide. The cause of this collapse is unclear, and it is attributed to an infectious synergy of multiple factors including pesticides, nutritional complications due to changes in climate patterns and diseases. ⁹ While viruses and fungal pathogens have been identified as good indicators of this condition, these pathogens, on their own, are not able to explain all losses, suggesting that honey bee colonies are suffering from compromised immune systems which pathogens

are able to take advantage of. ⁸ Two highly contagious diseases that affect bee (Apis mellifera) larvae worldwide demonstrates the magnitude of this problem: American and European Foulbrood. In the last two years, 53 countries suffered from these diseases ¹⁰ and 6 of them are among the top 10 honey producers. ¹¹

Detailed description

Methodology

Here we present the 8 steps our project involves, all the way from the beginning until the end. For additional information of each step, click on the images!