scholarly journals KofamKOALA: KEGG ortholog assignment based on profile HMM and adaptive score threshold

2019 ◽  
Author(s):  
Takuya Aramaki ◽  
Romain Blanc-Mathieu ◽  
Hisashi Endo ◽  
Koichi Ohkubo ◽  
Minoru Kanehisa ◽  
...  

AbstractSummaryKofamKOALA is a web server to assign KEGG Orthologs (KOs) to protein sequences by homology search against a database of profile hidden Markov models (KOfam) with pre-computed adaptive score thresholds. KofamKOALA is faster than existing KO assignment tools with its accuracy being comparable to the best performing tools. Function annotation by KofamKOALA helps linking genes to KEGG resources such as the KEGG pathway maps and facilitates molecular network reconstruction.AvailabilityKofamKOALA, KofamScan, and KOfam are freely available from https://www.genome.jp/tools/kofamkoala/[email protected]

2019 ◽  
Vol 36 (7) ◽  
pp. 2251-2252 ◽  
Author(s):  
Takuya Aramaki ◽  
Romain Blanc-Mathieu ◽  
Hisashi Endo ◽  
Koichi Ohkubo ◽  
Minoru Kanehisa ◽  
...  

Abstract Summary KofamKOALA is a web server to assign KEGG Orthologs (KOs) to protein sequences by homology search against a database of profile hidden Markov models (KOfam) with pre-computed adaptive score thresholds. KofamKOALA is faster than existing KO assignment tools with its accuracy being comparable to the best performing tools. Function annotation by KofamKOALA helps linking genes to KEGG resources such as the KEGG pathway maps and facilitates molecular network reconstruction. Availability and implementation KofamKOALA, KofamScan and KOfam are freely available from GenomeNet (https://www.genome.jp/tools/kofamkoala/). Supplementary information Supplementary data are available at Bioinformatics online.


Author(s):  
Pavle Goldstein ◽  
Maja Karaga ◽  
Mate Kosor ◽  
Ivana Nižetić ◽  
Marija Tadić ◽  
...  

2006 ◽  
Vol 04 (05) ◽  
pp. 959-980 ◽  
Author(s):  
CHENHONG ZHANG ◽  
MIKELIS G. BICKIS ◽  
FANG-XIANG WU ◽  
ANTHONY J. KUSALIK

Hidden Markov models (HMMs) are one of various methods that have been applied to prediction of major histo-compatibility complex (MHC) binding peptide. In terms of model topology, a fully-connected HMM (fcHMM) has the greatest potential to predict binders, at the cost of intensive computation. While a profile HMM (pHMM) performs dramatically fewer computations, it potentially merges overlapping patterns into one which results in some patterns being missed. In a profile HMM a state corresponds to a position on a peptide while in an fcHMM a state has no specific biological meaning. This work proposes optimally-connected HMMs (ocHMMs), which do not merge overlapping patterns and yet, by performing topological reductions, a model's connectivity is greatly reduced from an fcHMM. The parameters of ocHMMs are initialized using a novel amino acid grouping approach called "multiple property grouping." Each group represents a state in an ocHMM. The proposed ocHMMs are compared to a pHMM implementation using HMMER, based on performance tests on two MHC alleles HLA (Human Leukocyte Antigen)-A*0201 and HLA-B*3501. The results show that the heuristic approaches can be adjusted to make an ocHMM achieve higher predictive accuracy than HMMER. Hence, such obtained ocHMMs are worthy of trial for predicting MHC-binding peptides.


2004 ◽  
Vol 01 (04) ◽  
pp. 595-610 ◽  
Author(s):  
BROŇA BREJOVÁ ◽  
DANIEL G. BROWN ◽  
TOMÁŠ VINAŘ

Optimal spaced seeds were developed as a method to increase sensitivity of local alignment programs similar to BLASTN. Such seeds have been used before in the program PatternHunter, and have given improved sensitivity and running time relative to BLASTN in genome–genome comparison. We study the problem of computing optimal spaced seeds for detecting homologous coding regions in unannotated genomic sequences. By using well-chosen seeds, we are able to improve the sensitivity of coding sequence alignment over that of TBLASTX, while keeping runtime comparable to BLASTN. We identify good seeds by first giving effective hidden Markov models of conservation in alignments of homologous coding regions. We give an efficient algorithm to compute the optimal spaced seed when conservation patterns are generated by these models. Our results offer the hope of improved gene finding due to fewer missed exons in DNA/DNA comparison, and more effective homology search in general, and may have applications outside of bioinformatics.


2005 ◽  
Vol 21 (10) ◽  
pp. 2287-2293 ◽  
Author(s):  
R. Y. Kahsay ◽  
G. Wang ◽  
G. Gao ◽  
L. Liao ◽  
R. Dunbrack

2015 ◽  
Vol 135 (12) ◽  
pp. 1517-1523 ◽  
Author(s):  
Yicheng Jin ◽  
Takuto Sakuma ◽  
Shohei Kato ◽  
Tsutomu Kunitachi

Sign in / Sign up

Export Citation Format

Share Document