<s>
T-Coffee	B-Application
(	O
Tree-based	O
Consistency	O
Objective	O
Function	O
for	O
Alignment	O
Evaluation	O
)	O
is	O
a	O
multiple	O
sequence	B-Application
alignment	I-Application
software	I-Application
using	O
a	O
progressive	O
approach	O
.	O
</s>
<s>
It	O
produces	O
alignment	O
in	O
the	O
aln	O
format	O
(	O
Clustal	B-Application
)	O
by	O
default	O
,	O
but	O
can	O
also	O
produce	O
PIR	O
,	O
MSF	O
,	O
and	O
FASTA	B-Application
format	O
.	O
</s>
<s>
The	O
most	O
common	O
input	O
formats	O
are	O
supported	O
(	O
FASTA	B-Application
,	O
PIR	O
)	O
.	O
</s>
<s>
T-Coffee	B-Application
algorithm	O
consist	O
of	O
two	O
main	O
features	O
,	O
the	O
first	O
by	O
utilizing	O
heterogeneous	O
data	O
sources	O
it	O
is	O
able	O
to	O
provide	O
simple	O
and	O
flexible	O
means	O
of	O
generating	O
multiple	O
alignments	O
.	O
</s>
<s>
T-coffee	B-Application
can	O
compute	O
multiple	O
alignments	O
using	O
a	O
library	O
that	O
was	O
generated	O
using	O
a	O
mixture	O
of	O
local	O
and	O
global	O
pair-wise	O
alignments	O
.	O
</s>
<s>
The	O
second	O
is	O
the	O
"	O
Optimization	O
method	O
"	O
,	O
used	O
to	O
find	O
the	O
multiple	O
alignment	O
that	O
best	O
fits	O
the	O
pair-wise	O
alignments	O
in	O
the	O
input	O
library	O
using	O
a	O
progressive	O
strategy	O
that	O
can	O
be	O
compared	O
to	O
the	O
one	O
used	O
in	O
ClustalW	B-Application
.	O
</s>
<s>
Global	O
alignments	O
are	O
constructed	O
using	O
ClustalW	B-Application
on	O
the	O
sequences	O
,	O
two	O
at	O
a	O
time	O
,	O
and	O
sed	O
to	O
give	O
one	O
full-length	O
alignment	O
between	O
each	O
pair	O
of	O
sequences	O
.	O
</s>
<s>
The	O
local	O
alignments	O
are	O
the	O
ten	O
top-scoring	O
non-intersecting	O
local	O
alignments	O
gathered	O
using	O
the	O
Lalign	O
program	O
of	O
the	O
FASTA	B-Application
package	O
.	O
</s>
<s>
Efficient	O
combination	O
of	O
local	O
and	O
global	O
alignment	O
information	O
is	O
an	O
important	O
factor	O
of	O
T-Coffee	B-Application
.	O
</s>
<s>
By	O
using	O
the	O
ClustalW	B-Application
and	O
Lalign	O
primary	O
libraries	O
it	O
can	O
be	O
achieved	O
with	O
a	O
process	O
of	O
addition	O
.	O
</s>
<s>
Start	O
with	O
a	O
set	O
of	O
protein	O
or	O
nucleotide	O
sequences	O
that	O
you	O
want	O
to	O
align	O
using	O
T-Coffee	B-Application
.	O
</s>
<s>
Reliable	O
sources	O
for	O
T-Coffee	B-Application
parameters	O
and	O
their	O
usage	O
can	O
be	O
found	O
in	O
the	O
official	O
documentation	O
of	O
.	O
</s>
<s>
Install	O
and	O
run	O
T-Coffee	B-Application
on	O
your	O
local	O
machine	O
or	O
use	O
an	O
online	O
version	O
of	O
T-Coffee	B-Application
.	O
</s>
<s>
T-Coffee	B-Application
can	O
be	O
installed	O
on	O
various	O
operating	O
systems	O
,	O
such	O
as	O
Windows	O
,	O
</s>
<s>
Online	O
versions	O
of	O
T-Coffee	B-Application
is	O
available	O
at	O
.	O
</s>
<s>
Analyze	O
the	O
output	O
results	O
generated	O
by	O
T-Coffee	B-Application
to	O
interpret	O
the	O
alignment	O
.	O
</s>
<s>
While	O
the	O
default	O
output	O
is	O
a	O
Clustal-like	O
format	O
,	O
it	O
is	O
sufficiently	O
different	O
from	O
the	O
output	O
of	O
ClustalW/X	O
that	O
many	O
programs	O
supporting	O
Clustal	B-Application
format	O
cannot	O
read	O
it	O
;	O
fortunately	O
ClustalX	B-Application
can	O
import	O
T-Coffee	B-Application
output	O
so	O
the	O
simplest	O
fix	O
for	O
this	O
issue	O
is	O
usually	O
to	O
import	O
T-Coffee	B-Application
'	O
s	O
output	O
into	O
ClustalX	B-Application
and	O
then	O
re-export	O
.	O
</s>
<s>
Another	O
possibility	O
is	O
to	O
request	O
the	O
strict	O
Clustalw	B-Application
output	O
format	O
with	O
the	O
option	O
"	O
-output	O
=	O
clustalw_aln	O
"	O
.	O
</s>
<s>
An	O
important	O
specificity	O
of	O
T-Coffee	B-Application
is	O
its	O
ability	O
to	O
combine	O
different	O
methods	O
and	O
different	O
data	O
types	O
.	O
</s>
<s>
In	O
its	O
latest	O
version	O
,	O
T-Coffee	B-Application
can	O
be	O
used	O
to	O
combine	O
protein	O
sequences	O
and	O
structures	O
,	O
RNA	O
sequences	O
and	O
structures	O
.	O
</s>
<s>
T-Coffee	B-Application
comes	O
along	O
with	O
a	O
sophisticated	O
sequence	O
reformatting	O
utility	O
named	O
seq_reformat	O
.	O
</s>
<s>
T-Coffee	B-Application
has	O
been	O
widely	O
used	O
for	O
phylogenetic	O
analysis	O
,	O
as	O
it	O
can	O
provide	O
high-quality	O
alignments	O
of	O
protein	O
or	O
DNA	O
sequences	O
that	O
are	O
required	O
for	O
accurate	O
reconstruction	O
of	O
evolutionary	O
relationships	O
.	O
</s>
<s>
T-Coffee	B-Application
can	O
be	O
used	O
for	O
comparative	O
modeling	O
of	O
protein	O
structures	O
,	O
as	O
accurate	O
alignments	O
of	O
protein	O
sequences	O
are	O
essential	O
for	O
successful	O
modeling	O
.	O
</s>
<s>
T-Coffee	B-Application
can	O
be	O
used	O
for	O
functional	O
annotation	O
of	O
proteins	O
by	O
identifying	O
conserved	O
domains	O
and	O
motifs	O
across	O
different	O
protein	O
families	O
.	O
</s>
<s>
T-Coffee	B-Application
can	O
be	O
used	O
for	O
genome	O
annotation	O
by	O
aligning	O
the	O
protein-coding	O
sequences	O
of	O
a	O
genome	O
to	O
identify	O
gene	O
structures	O
and	O
exon-intron	O
boundaries	O
.	O
</s>
<s>
T-Coffee	B-Application
can	O
be	O
used	O
for	O
multiple	O
sequence	O
alignment	O
of	O
metagenomic	O
data	O
,	O
which	O
comprises	O
sequences	O
from	O
various	O
microbial	O
species	O
in	O
a	O
community	O
.	O
</s>
<s>
It	O
is	O
a	O
meta	O
server	O
that	O
combines	O
the	O
output	O
of	O
multiple	O
alignment	O
methods	O
,	O
including	O
T-Coffee	B-Application
,	O
to	O
improve	O
the	O
accuracy	O
of	O
the	O
final	O
alignment	O
.	O
</s>
<s>
Expresso	O
is	O
a	O
plugin	O
that	O
integrates	O
T-Coffee	B-Application
with	O
several	O
other	O
alignment	O
methods	O
,	O
including	O
Clustal	B-Application
Omega	I-Application
,	O
MAFFT	B-Application
,	O
and	O
Muscle	B-Application
,	O
to	O
improve	O
the	O
accuracy	O
of	O
the	O
final	O
alignment	O
.	O
</s>
<s>
M-Coffee	O
:	O
a	O
special	O
mode	O
of	O
T-Coffee	B-Application
that	O
makes	O
it	O
possible	O
to	O
combine	O
the	O
output	O
of	O
the	O
most	O
common	O
multiple	O
sequence	O
alignment	O
packages	O
(	O
Muscle	B-Application
,	O
ClustalW	B-Application
,	O
Mafft	B-Application
,	O
ProbCons	O
,	O
etc	O
.	O
)	O
.	O
</s>
<s>
Expresso	O
and	O
3D-Coffee	O
:	O
these	O
are	O
special	O
modes	O
of	O
T-Coffee	B-Application
making	O
it	O
possible	O
to	O
combine	O
sequence	O
and	O
structures	O
in	O
an	O
alignment	O
.	O
</s>
<s>
R-Coffee	O
:	O
a	O
special	O
mode	O
of	O
T-Coffee	B-Application
making	O
it	O
possible	O
to	O
align	O
RNA	O
sequences	O
while	O
using	O
secondary	O
structure	O
information	O
.	O
</s>
<s>
Four	O
different	O
evaluation	O
programs	O
come	O
with	O
the	O
T-Coffee	B-Application
software	O
,	O
including	O
TCS	O
,	O
iRMSD	O
,	O
T-RMSD	O
,	O
and	O
STRIKE	O
.	O
</s>
<s>
(	O
Transitive	O
Consistency	O
Score	O
)	O
is	O
an	O
extended	O
version	O
of	O
the	O
T-Coffee	B-Application
scoring	O
scheme	O
.	O
</s>
<s>
It	O
uses	O
T-Coffee	B-Application
libraries	O
of	O
pairwise	O
alignments	O
to	O
evaluate	O
any	O
third	O
party	O
MSA	O
.	O
</s>
<s>
When	O
T-Coffee	B-Application
is	O
run	O
,	O
it	O
automatically	O
evaluates	O
and	O
shows	O
various	O
scores	O
of	O
the	O
generated	O
MSA	O
based	O
on	O
the	O
Transitive	O
Consistency	O
Score	O
(	O
TCS	O
)	O
.	O
</s>
<s>
These	O
scores	O
are	O
created	O
by	O
building	O
T-Coffee	B-Application
libraries	O
using	O
multiple	O
methods	O
,	O
but	O
a	O
hidden	O
Markov	O
model	O
is	O
used	O
by	O
default	O
.	O
</s>
<s>
The	O
last	O
scoring	O
method	O
included	O
with	O
T-Coffee	B-Application
is	O
Single	O
sTRucture	O
Induced	O
Evaluation	O
(	O
STRIKE	O
)	O
,	O
which	O
creates	O
a	O
matrix	O
similar	O
to	O
BLOSUM	O
and	O
requires	O
a	O
base	O
template	O
to	O
compare	O
an	O
alignment	O
against	O
.	O
</s>
<s>
T-Coffee	B-Application
alignment	O
can	O
be	O
affected	O
by	O
several	O
challenges	O
,	O
particularly	O
the	O
quality	O
of	O
input	O
sequences	O
and	O
their	O
significant	O
gaps	O
.	O
</s>
<s>
Additionally	O
,	O
T-Coffee	B-Application
alignment	O
may	O
struggle	O
to	O
align	O
highly	O
divergent	O
sequences	O
,	O
making	O
it	O
difficult	O
to	O
identify	O
homologous	O
regions	O
between	O
them	O
.	O
</s>
<s>
The	O
computational	O
demands	O
of	O
T-Coffee	B-Application
alignment	O
can	O
limit	O
its	O
scalability	O
and	O
make	O
it	O
time-consuming	O
,	O
particularly	O
when	O
aligning	O
large	O
datasets	O
,	O
which	O
can	O
limit	O
its	O
usefulness	O
for	O
large-scale	O
analyses	O
.	O
</s>
