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Determination of the pandemic potential of the H5N1 virus with bioinformatic

methods

Marko Tumbas
Center for talented youth Belgrade II, Belgrade, tumbasm@gmail.com

from 1996 as well as the characteristic sequences from
1. Introduction 2006 that shows the evolution of HA1 and his affinity for
the human receptor (Figure 2).
The H5N1 virus was first isolated in 1996 in Hong Kong
during outbreaks among poultry. Since then it has been its
geographic expansion and adaptation to greater efficiency
of transmission to humans. The most important protein of
the H5N1 virus is hemagglutinin[1]. One of its two
subunits, the HA1, has a role in the cell receptors binding.
HA1 has spectral characteristics that are reflected in the Figure 2 – HA1 protein sequences with the IS method
efficiency of transmission. Frequency F(0.076) corresponds A – 1996 Guandong goose, B- 2006 Nigeria chicken 24
to the animal and F(0.236) with the human receptor.
Analysis of proteins of the influenza virus H5N1 have C – 2006 Germany duck, D – 2006 Nigeria Chicken 38
shown that there may be mutations in the HA1 part of
protein that would affect its pandemic potential.

2. Materials and methods Figure 3 – Part of the aligned sequences 241-260
Multiple alignment of sequences is showing a mutations
In this research we used hemagglutinin protein sequences which have a variety of effects on the protein (Figure 3).
isolated since 1996. Sequences were downloaded from the Predictions that would lead to an extreme increase of the
website Influenza Virus Resource[2]. The HA1 subunits 0.236/0.076 ratio are conducted on the last available
were segregated from the sequences. ISM tree program[3] sequences. The spectra of the potentially most problematic
is used to determine the evolutionary tree. Sequence mutations are shown in Figure 4.
similarity is based on the ratio between frequency 0.256
and 0.076. Priority was given to the ratio of HA1 sequences
that is greater than F(0.236)/F(0.076)>1. For the further
2
analysis of the sequences is used χ test. Individual
sequences are graphically displayed using IS method. Then
these typical examples were subjected to the multiple
sequence alignments [4]. Monitoring and prediction of
mutations that would lead to an increase in the ratio Figure 4 – Predicting the effects of mutations
0.236/0.076 is conducted by AK scanner.
A – D54A, B – F290I, C – I284R
4. Conclusion
3. Results and discussion
The results show us that the greatest pandemic potential
Evolutionary tree was used to select the important until now have sequences from Egypt, Nigeria and
sequences and locate infection hot spots. On the Germany. The largest number of sequences with a value of
evolutionary tree there are three groups of sequences with F(0.236)/F(0076)>1 was in 2006. That corresponds to the
the ratio F(0236)/F(0076)>1 They are originally from peak of infection. Mutations at positions 54, 284 and 290 of
Germany, Egypt and Nigeria (Figure 1). HA1 protein may lead to an increase in the potential and
trigger a new infection.

5. References

Figuree 1 – The sequences of the amplitude ratio F [1] V. Veljkovic, N. Veljkovic, C.P. Muller, S. Muller, S.
Glisic, V. Perovic, H. Kohler. BMC Struct Biol. 9, (2009),
(0236) / F (0076)> 1
[2] Y. Bao, P. Bolotov, D. Dernovoy, B. Kiryutin, L.
The obtained data indicate a significant change in the Zaslavsky, T. Tatusova, J Virol. 82, (2008), 596-601.
number of sequences with a ratio F(0236)/F(0076)>1 over [3] V.R. Perovic, C.P. Muller, H.L. Niman, N. Veljkovic,
the years. The results are consistent with data from the U. Dietrich, D.D. Tosic, S. PLoS One. 8, (2013), e61572.
World Health Organization on the number of recorded [4] F. Sievers, A. Wilm, D. Dineen, T.J. Gibson, K.
cases. Analyzed sequences belong to the original sequence Karplus, W. Li, R. Lopez, H. McWilliam, M. Remmert ET
AL. Mol Syst Biol. 7 (2011), 539.