Journal of Agricultural and Food Chemistry,
Journal Year:
2024,
Volume and Issue:
unknown
Published: Dec. 19, 2024
Difucosyllactose
(DFL),
an
important
kind
of
fucosylated
human
milk
oligosaccharides
(HMOs),
has
garnered
considerable
attention
due
to
its
excellent
physiological
activities
in
infants.
Previously,
we
achieved
de
novo
biosynthesis
DFL;
however,
substantial
residual
intermediates
fucosyllactoses
(FL)
were
detected.
In
this
study,
DFL
was
optimized,
and
FL
reduced
by
regulating
metabolic
pathways.
Different
plasmid
combinations
used
regulate
gene
expression,
achieving
optimal
flux
balance
between
2′-FL
DFL.
The
expression
level
key
enzyme
α-1,3-fucosyltransferase
(α-1,3-FT,
FucTa)
then
enhanced
increasing
copy
number
integrating
fucTa
into
the
chromosome.
Exocytosis
deleting
sugar
efflux
transporter
setA
gene,
thereby
minimizing
FL.
Finally,
strain
BSF41
produced
55.3
g/L
with
only
2.59
a
5
L
fermentor,
representing
highest
reported
titer
date.
This
study
provides
foundation
for
advancing
HMOs.
Journal of Agricultural and Food Chemistry,
Journal Year:
2024,
Volume and Issue:
72(13), P. 7179 - 7186
Published: March 23, 2024
Lacto-N-neotetraose
(LNnT),
a
prominent
neutral
human
milk
oligosaccharide
(HMO),
serves
as
pivotal
structural
element
in
complex
HMO
biosynthesis.
Given
its
promising
health
effects
for
infants,
the
biosynthesis
of
LNnT
is
garnering
greater
interest.
Using
previously
engineered
strain
chassis,
highly
effective
producer
was
constructed.
First,
synthesis
Escherichia
coli
MG1655
achieved
by
introducing
β1,3-N-acetylglucosaminyltransferase
LgtA
and
β1,4-galactosyltransferase
CpsIaJ,
coupled
with
optimization
enzyme
expression
levels
using
various
promoters.
Subsequently,
ugd
underwent
disruption,
galE
gene
enhanced
replacing
promoter
PJ23119
or
Ptac.
Then,
lux-type
quorum
sensing
(QS)
system
applied
to
achieve
varied
metabolic
regulation.
Additionally,
systematic
QS
promoters
conducted
further
improve
titer
shake
flask.
Finally,
extracellular
20.33
g/L,
accompanied
productivity
0.41
g/L/h.
ACS Sustainable Chemistry & Engineering,
Journal Year:
2024,
Volume and Issue:
12(17), P. 6619 - 6628
Published: April 17, 2024
l-Fucose
is
an
important
monosaccharide
unit
that
exists
in
various
biomasses,
especially
microalgae.
Microbial
l-fucose
using
metabolically
engineered
strains
has
attracted
attention
due
to
its
high
yield
and
industrial
feasibility.
Previously,
we
Escherichia
coli
MG1655
efficiently
produce
2′-fucosyllactose
by
genomic
integration.
Herein,
this
plasmid-free
strain
was
further
integrating
a
specific
α-l-fucosidase
gene
deleting
the
degradation
pathway.
Its
effectiveness
of
biosynthesis
inducer-free
fermentation
demonstrated
both
shake-flask
fed-batch
cultivation
with
titers
2.74
21.15
g/L,
respectively.
The
precursor
GDP-l-fucose
supply
strengthened
obviously
enhance
introducing
single
plasmid
expressing
four
pathway
genes.
hok/sok
system
introduced
promote
stabilization
without
antibiotic.
final
could
antibiotics,
6.83
35.68
g/L
fed-cultivation
cultivation,
Journal of Agricultural and Food Chemistry,
Journal Year:
2025,
Volume and Issue:
73(9), P. 5405 - 5413
Published: Feb. 24, 2025
Difucosyllactose
(DFL),
a
representative
bisfucosylated
oligosaccharide
found
in
human
milk,
has
garnered
significant
attention
due
to
its
immense
health
benefits.
To
date,
several
plasmid-based
engineered
strains
have
been
established
for
DFL
synthesis.
However,
these
face
challenges
such
as
antibiotic
dependence
and
plasmid
instability,
which
limit
their
commercial
application
the
food
industry.
For
this,
plasmid-free
Escherichia
coli
MG1655
were
by
integrating
multicopy
numbers
of
SAMT
fut3Bc
into
genome
overexpressing
key
genes
involved
GDP-l-fucose
pathway.
enhance
catalytic
efficiency,
Fut3Bc
was
mutated
based
on
AlphaFold
3,
obtaining
beneficial
mutant
(F24Y).
The
optimized
strain,
MGA2S-5,
containing
2
copies
4
(F24Y)
obtained.
Eventually,
strain
MGA2S-5
synthesized
35.04
g/L
7
L
bioreactor
fed-batch
cultivation,
with
no
intermediate
products
remaining
medium.
Scientific Reports,
Journal Year:
2024,
Volume and Issue:
14(1)
Published: July 31, 2024
Serratia
marcescens
is
an
opportunistic
human
pathogen
that
produces
a
vibrant
red
pigment
called
prodigiosin.
Prodigiosin
has
implications
in
virulence
of
S.
and
promising
clinical
applications.
We
discovered
addition
the
virulent
flagellotropic
bacteriophage
χ
(Chi)
to
culture
stimulates
greater
than
fivefold
overproduction
Active
phage
infection
required
for
effect,
as
χ-resistant
strain
lacking
flagella
does
not
respond
presence.
Via
reporter
fusion
assay,
we
have
determined
χ-induced
cell
lysate
uninfected
causes
threefold
increase
transcription
pig
operon,
containing
genes
essential
biosynthesis.
Replacement
promoter
with
constitutive
abolished
pigmentation
increase,
indicating
regulatory
elements
present
likely
mediate
phenomenon.
hypothesize
detects
threat
phage-mediated
death
reacts
by
producing
prodigiosin
stress
response.
Our
findings
are
significance
two
main
reasons:
(i)
elucidating
complex
phage-host
interactions
crucial
development
therapeutic
treatments,
(ii)
response
could
be
exploited
its
biosynthesis
use
pharmaceutical.
Journal of Agricultural and Food Chemistry,
Journal Year:
2025,
Volume and Issue:
73(9), P. 5385 - 5394
Published: Feb. 19, 2025
3-Fucosyllactose
(3-FL),
an
essential
component
of
human
milk
oligosaccharides,
is
crucial
for
infant
health.
However,
the
extraction
3-FL
from
presents
a
significant
challenge.
In
this
study,
E.
coli
BL21
Star
(DE3)
was
engineered
biosynthesis,
and
gene
combinations
metabolic
pathways
were
optimized
to
obtain
high-yield
production
strain.
First,
module
integrated
into
coli.
Second,
efficient
alpha-1,3-fucosyltransferase
screened.
Then,
different
integration
sites
used
optimize
precursor
synthesis
cluster
transferase
genes
screen
transporter
proteins
glycerol
utilization
that
could
enhance
production.
The
3FL05-1
strain
yielded
titer
11.26
g/L
in
shake
flasks.
Further
amplification
5
L
bioreactor
resulted
60.24
g/L,
which
represents
highest
reported
date.
