The document summarizes the baculovirus expression vector system (BEVS), which uses baculoviruses to express recombinant proteins in insect cells. Key aspects covered include: Baculoviruses naturally infecting lepidopteran insects; a donor plasmid containing the gene of interest being inserted into a bacmid shuttle vector containing the baculovirus genome; transfecting insect cells with the bacmid leading to viral production and protein expression; and serially passaging the virus to produce high titers for large-scale protein expression. The system provides an alternative to prokaryotic expression when eukaryotic processing is required.

1. -Efforts by
Gunali Chaudhari
(218238)
Baculovirus Expression Vector System
(BEVS)

2. INTRODUCTION
 The baculovirus vector system is widely used for the expression of recombinant proteins in
cultured insect cells.
 It is one of the most versatile and powerful systems for eukaryotic expression of
recombinant proteins.
 This system is particularly advantageous for large-scale preparation of proteins that require
expression in eukaryotic host cells.
 In these cases, prokaryotic expression systems are often inadequate and the baculovirus
expression system could be a good alternative.
 The shuttle vector is called bacmid, and gene expression is under the control of a strong
promoter pPolh.
 Baculovirus has also been used with mammalian cell lines known as BacMam system.
Baculovirus –
• Envelop, double –stranded DNA
virus
• Belongs to baculoviridae family
• Most widely used baculovirus
species is Autographa Californica
multiple nucleopolyhedrovirus
(AcMNPV)
• Mostly infects Lepidopterans
(moths and butterflies) such as
Spodoptera frugiperda and Bmbyx
mori. Image credit - Berretta, M. F. , Baculovirus gene expression.

3. DONOR
PLASMID
• Multiple cloning site
• pUC origin
• Tn7R
• Ampicillin resistance
gene
• Fi origin (fi intergenic
region)
• Polyhedrin promoter
(PPH)
• Gentamicin resistance
gene
• SV40 polyadenylation
signal
• Tn7L
Image courtesy - https://www.thermofisher.com/order/catalog/product/10360014

4. BACMID
• Shuttle vector
• The bacmid is essentially a very large
plasmid containing the baculovirus
genome modified to carry a lacZ gene.
• attTn7 (a short segment containing the
attachment site for the bacterial
transposon Tn7 ) inserted in the lacZ
coding region.
• Kanamycin resistance marker
• A low copy number mini- fertily replicon.
• Transposition is the process by which
genetic elements move between different
locations of the genome.
https://en.vectorbuilder.com/resources/vector-
system/pBV.html
Image courtesy -

5. Image credits - Sui, Dong & Wang, Kuanquan & Park, Heemin & Chae, Jinseok. (2014). Bright field
microscopic cells counting method for BEVS using nonlinear convergence index sliding band filter.
Biomedical engineering online. 13. 147. 10.1186/1475-925X-13-147.

6. PROTOCOL
Serial Passage –
• Serial passage is the
process of growing
bacteria or a virus in
iterations or repetition.
• A virus may be grown in
one environment, and
then a portion of that virus
population can be
removed and put into a
new environment.
• P0 – The virus progeny
from a transfection or
cotransfection.
• P1- Second generation of
the virus

7. References
 Mena, J. A. , Kamen, A. A. , Insect cell technology is a versatile
and robust vaccine manufacturing platform. Expert Rev. Vaccines
2011, 10, 1063–1081.
 Hu, Y. C. , Baculovirus as a highly efficient expression vector in
insect and mammalian cells. Acta Pharmacol. Sin. 2005, 26,
405–416.
 Wickham, T. J. , Davis, T. , Granados, R. R. , Shuler, M. L. ,
Wood, H. A. , Screening of insect cell lines for the production of
recombinant proteins and infectious virus in the baculovirus
expression.
 https://www.news-medical.net/life-sciences/The-Baculovirus-
Expression-Vector-System-(BEVS).aspx
 https://www.sciencedirect.com/topics/medicine-and-
dentistry/baculovirus-expression-system
 https://en.vectorbuilder.com/resources/vector-system/pBV.html