Dr Khawar Sohail Siddiqui
Project Officer

Dr Khawar Sohail Siddiqui

PhD: (Biotechnology) Imperial College, London, UK

MSc: (Zoological Sciences) Peshawar University, Pakistan

BSc: (Biology, Chemistry, English) Sadiq-Egerton College, Bahawalpur, Pakistan

Biotech & Biomolecular Science

Professional Experience

  • Nov 2019 - ongoing: School of Biotechnology & Biomolecular Sciences (BABS), University of New South Wales, Sydney. Project Officer
  • Aug 2014-aug 2019: Life Science Dept. King Fahd University of Petroleum and Minerals (KFUPM), Dhahran, Saudi Arabia. Associate Professor
  • Jan-2005 to July 2014: School of Biotechnology & Biomolecular Sciences (BABS), University of New South Wales, Sydney. Senior Research Associate
  • 15-8-2004 to 5-1-2005: Biosciences Dept, COMSATS Institute of Information Technology, Islamabad, Pakistan. Visiting Professor
  • Feb-2001 to Aug-2004: School of Biotechnology & Biomolecular Sciences, UNSW, Sydney, Australia. Senior Research Associate
  • 26-2-2001 - 4-6-2001: Biochemistry Dept, Sydney University, Sydney.Teaching Demonstration
  • 1999-2000: Protein Chemistry Division, Pharmaceuticals Research Centre, King Abdul-Asia City of Science and Technology, (SPIMACO), Riyadh, Saudi Arabia in collaboration with Orpegen Therapeutika, Germany Research Specialist
  • 1990-1999: National Institute for Biotechnology and Genetic Engineering, (NIBGE), Jhang Road, Faisalabad, Pakistan.Senior Scientific Officer
  • 1986-1990: Centre for  Biotechnology, Imperial College, London . PhD student


Research Contribution

My field of research involves protein chemistry and biocatalysis using enzymes. The information gained from the bioinformatic, kinetic and thermodynamic characterization of native, chemically and genetically modified enzymes is utilized for the elucidation of protein structure-function-stability relationship. I am currently working on Biochemical analysis in tissues, enzymes that are implicated in the production of glutathione and bioinformatics screening of plant molecules as the inhibitors for the main protease of COVID-19 virus. In addition I employed extremophilic enzymes  from Antarctica's cold adapted organisms in order to enhance their stability while keeping their high intrinsic activity. Conversely, I enhanced the activity of industrially important thermophilic protease at low temperatures by chemical modification. I apply native and improved enzymes for treating waste-waters as well as for cleaning fouled membranes. 

For purification and characterisation of proteins we employ a variety of biochemical and biophysical techniques such as chromatography, electrophoresis, UV-Vis spectrometry, spectropolarimetry, fluorimetry and calorimetry (differential scanning and isothermal titration calorimetry). In addition we employ methods such as small-angle X-ray scattering (SAXS), mass spectrometry and X-ray diffraction crystallography in collaboration with other groups.

  • Cited among Top Scientists of the Country published by Pakistan Council of Science & Technology - February 2001
  • Invited review in many high impact journals
  • Co-edit a book entitled "Protein adaption in extremophiles" published by Nova Science Publisher - New York, USA (2008)
  • Best Teacher's Certificate (MPhil Biotechnology) awarded by National Institute of Biotechnology and Genetic Engineering - Faisalabad, Pakistan (1995-1998)
  • Written four text book chapters with other colleagues
  • Reviewer for many biochemical and biotechnology journals of international repute
  • Cited on the cover of Uniken - UNSW, Sydney, Australia
  • PhD Scholarship awarded by Ministry of Science & Technology - Pakistan (1986)
+61 0470538639
Room 420, Level 4, BABS (Office) Room 403, Level 4, BABS (Lab)


  • Book Chapters | 2017
    Siddiqui KS; Shemsi AM; Guerriero G; Najnin T; Taha ; Ertan H, 2017, 'Biotechnological improvements of cold- adapted enzymes: Commercialization via an integrated approach', in Psychrophiles: From Biodiversity to Biotechnology: Second Edition, pp. 477 - 512, http://dx.doi.org/10.1007/978-3-319-57057-0_20
    Books | 2008
    2008, Protein Adaptation in Extremophiles, Siddiqui KS; Thomas T, (ed.), Original, Nova Biomedical Books, New York, https://www.novapublishers.com/catalog/product_info.php?cPath=23_29&products_id=6238&osCsid=523411be245aa875dc809b66c2ebf54b
    Book Chapters | 2008
    Kato C; Sato T; Abe F; Ohmae E; Tamegai H; Nakasone K; Siddiqui KS; Thomas T, 2008, 'Protein Adaptation to High-Pressure Environments', in Protein Adaptation in Extremophiles, edn. Original, Nova Biomedical Books, New York, pp. 167 - 192
    Book Chapters | 2006
    Cavicchioli R; Curmi PMG; Siddiqui KS; Thomas T, 2006, '17 Proteins from Psychrophiles', in Methods in Microbiology, edn. Original, Elsevier, London, England, pp. 395 - 436, http://dx.doi.org/10.1016/S0580-9517(08)70020-5
    Book Chapters | 2004
    Cavicchioli R; Siddiqui KS, 2004, 'Cold-adapted enzymes', in Pandey A; Webb C; Soccol CR; Larroche C (ed.), Enzyme Technology, edn. Original, Asiatech Publishers, Inc., New Delhi, pp. 615 - 638
  • Journal articles | 2016
    Guerriero G; Hausman JF; Strauss J; Ertan H; Siddiqui KS, 2016, 'Lignocellulosic biomass: Biosynthesis, degradation, and industrial utilization', Engineering in Life Sciences, vol. 16, pp. 1 - 16, http://dx.doi.org/10.1002/elsc.201400196
    Journal articles | 2015
    Guerriero G; Hausman JF; Strauss J; Ertan H; Siddiqui KS, 2015, 'Destructuring plant biomass: Focus on fungal and extremophilic cell wall hydrolases', Plant Science, vol. 234, pp. 180 - 193, http://dx.doi.org/10.1016/j.plantsci.2015.02.010
    Journal articles | 2014
    Das T; Sehar S; Koop L; Wong YK; Ahmed S; Siddiqui KS; Manefield M, 2014, 'Influence of calcium in extracellular DNA mediated bacterial aggregation and biofilm formation', PLoS ONE, vol. 9, http://dx.doi.org/10.1371/journal.pone.0091935
    Journal articles | 2021
    Ang DL; Hoque MZ; Hossain MA; Guerriero G; Berni R; Hausman JF; Bokhari SA; Bridge WJ; Siddiqui KS, 2021, 'Computational analysis of thermal adaptation in extremophilic chitinases: The achilles’ heel in protein structure and industrial utilization', Molecules, vol. 26, http://dx.doi.org/10.3390/molecules26030707
    Journal articles | 2021
    Mushtaq U; Bhat SS; Parray AA; Nabi S; Wani AH; Qurashi AH; Siddiqui KS; Khanday FA, 2021, 'A simple, economical and environmental-friendly method for staining protein gels using an extract from walnut-husk', Chemico-Biological Interactions, vol. 333, http://dx.doi.org/10.1016/j.cbi.2020.109310
    Journal articles | 2017
    Jayawardena MB; Yee LH; Poljak A; Cavicchioli R; Kjelleberg SJ; Siddiqui KS, 2017, 'Enhancement of lipase stability and productivity through chemical modification and its application to latex-based polymer emulsions', Process Biochemistry, vol. 57, pp. 131 - 140, http://dx.doi.org/10.1016/j.procbio.2017.03.014
    Journal articles | 2016
    Taha ; Siddiqui KS; Campanaro S; Najnin T; Deshpande N; Williams TJ; Aldrich-Wright J; Wilkins M; Curmi PMG; Cavicchioli R, 2016, 'Single TRAM domain RNA-binding proteins in Archaea: functional insight from Ctr3 from the Antarctic methanogen Methanococcoides burtonii', Environmental microbiology, vol. 18, pp. 2810 - 2824, http://dx.doi.org/10.1111/1462-2920.13229
    Journal articles | 2016
    Najnin T; Siddiqui KS; Taha ; Elkaid N; Kornfeld G; Curmi PMG; Cavicchioli R, 2016, 'Characterization of a temperature-responsive two component regulatory system from the Antarctic archaeon, Methanococcoides burtonii', Scientific Reports, vol. 6, http://dx.doi.org/10.1038/srep24278
    Journal articles | 2016
    Najnin T; Siddiqui KS; Taha ; Elkaid N; Kornfeld G; Curmi PMG; Cavicchioli R, 2016, 'Erratum: Characterization of a temperature-responsive two component regulatory system from the Antarctic archaeon, Methanococcoides burtonii (Scientific Reports (2016) 6 (24278) DOI: 10.1038/srep24278)', Scientific Reports, vol. 6, http://dx.doi.org/10.1038/srep27162
    Journal articles | 2015
    Ertan H; Cassel C; Verma A; Poljak A; Charlton T; Aldrich-Wright J; Omar SM; Siddiqui KS; Cavicchioli R, 2015, 'A new broad specificity alkaline metalloprotease from a Pseudomonas sp. isolated from refrigerated milk: Role of calcium in improving enzyme productivity', Journal of Molecular Catalysis B: Enzymatic, vol. 113, pp. 1 - 8, http://dx.doi.org/10.1016/j.molcatb.2014.12.010
    Journal articles | 2014
    Siddiqui KS; Ertan H; Charlton T; Poljakc A; Khaled AK; Yang X; Marshall G; Cavicchioli R, 2014, 'Versatile peroxidase degradation of humic substances: Use of isothermal titration calorimetry to assess kinetics, and applications to industrial wastes', Journal of Biotechnology, vol. 178, pp. 1 - 11, http://dx.doi.org/10.1016/j.jbiotec.2014.03.002
    Journal articles | 2012
    Muenchhoff J; Siddiqui KS; Neilan BA, 2012, 'Identification of two residues essential for the stringent substrate specificity and active site stability of the prokaryotic l -arginine:glycine amidinotransferase CyrA', FEBS Journal, vol. 279, pp. 805 - 815, http://dx.doi.org/10.1111/j.1742-4658.2012.08472.x
    Journal articles | 2010
    Muenchhoff J; Siddiqui KS; Poljak A; Raftery MJ; Barrow KD; Neilan BA, 2010, 'A novel prokaryotic L-arginine:glycine amidinotransferase is involved in cylindrospermopsin biosynthesis', FEBS Journal, vol. 277, pp. 3844 - 3860, http://dx.doi.org/10.1111/j.1742-4658.2010.07788.x
    Journal articles | 2009
    Allen MA; Lauro FM; Williams TJ; Burg DW; Siddiqui KS; De Francisci D; Chong K; Pilak O; Chew H; De Maere M; Ting LL; Katrib M; Ng SC; Sowers KR; Galperin M; Anderson I; Ivanova N; Dalin E; Martinez MP; Lapidus A; Hauser L; Land MH; Thomas T; Cavicchioli R, 2009, 'The genome sequence of the psychrophilic archaeon, Methanococcoides burtonii: The role of genome evolution in cold adaptation', ISME Journal, vol. 3, pp. 1012 - 1035, http://dx.doi.org/10.1038/ismej.2009.45
    Journal articles | 2009
    Siddiqui KS; Parkin DM; Curmi PM; De Francisci D; Poljak A; Barrow KD; Noble M; Trewhella J; Cavicchioli R, 2009, 'A novel approach for enhancing the catalytic efficiency of a protease at low temperature: Reduction in substrate inhibition by chemical modification', Biotechnology and Bioengineering, vol. 103, pp. 676 - 686, http://dx.doi.org/10.1002/bit.22300
    Journal articles | 2008
    Afzal AJ; Bokhari SA; Siddiqui KS, 2008, 'Erratum: Kinetic and thermodynamic study of a chemically modified highly active xylanase from scopulariopsis sp (Applied Biochemistry and Biotechnology))', Applied Biochemistry and Biotechnology, vol. 150, pp. 113, http://dx.doi.org/10.1007/s12010-008-8157-8
    Journal articles | 2007
    Afzal A; Bokhari S; Siddiqui KS, 2007, 'Kinetic and thermodynamic study of a chemically modified highly active xylanase from Scopulariopsis sp - Existence of an essential amino group', Applied Biochemistry and Biotechnology, vol. 141, pp. 273 - 297, https://www.ncbi.nlm.nih.gov/pubmed/18025557
    Journal articles | 2007
    Giaquinto L; Curmi PM; Siddiqui KS; Poljak A; DeLong E; DasSarma S; Cavicchioli R, 2007, 'Structure and function of cold shock proteins in archaea', Journal of Bacteriology, vol. 189, pp. 5738 - 5748, http://dx.doi.org/10.1128/JB.00395-07
    Journal articles | 2007
    Afzal AJ; Bokhari SA; Siddiqui KS, 2007, 'Kinetic and thermodynamic study of a chemically modified highly active xylanase from Scopulariopsis sp.', Applied Biochemistry and Biotechnology, vol. 141, pp. 273 - 297, http://dx.doi.org/10.1007/BF02729068
    Journal articles | 2006
    Siddiqui KS; Cavicchioli R, 2006, 'Cold-adapted enzymes', Annual Review of Biochemistry, vol. 75, pp. 403 - 433, http://dx.doi.org/10.1146/annurev.biochem.75.103004.142723
    Journal articles | 2006
    Siddiqui KS; Poljak A; Guilhaus M; De Francisci D; Curmi PM; Feller G; D Amico S; Gerday C; Uversky V; Cavicchioli R, 2006, 'Role of lysine versus arginine in enzyme cold-adaptation: Modifying lysine to homo-arginine stabilizes the cold-adapted alpha-amylase from Pseudoalteramonas haloplanktis', Proteins - Structure Function and Bioinformatics, vol. 64, pp. 486 - 501, http://dx.doi.org/10.1002/prot.20989
    Journal articles | 2005
    Siddiqui KS; Feller G; D Amico S; Gerday C; Giaquinto L; Cavicchioli R, 2005, 'The active site is the least stable structure in the unfolding pathway of a multidomain cold-adapted alpha-amylase', Journal of Bacteriology, vol. 187, pp. 6197 - 6205, http://dx.doi.org/10.1128/JB.187.17.6197-6205.2005
    Journal articles | 2005
    Siddiqui KS; Cavicchioli R, 2005, 'Improved thermal stability and activity in the cold-adapted lipase B from Candida antarctica following chemical modification with oxidized polysaccharides', Extremophiles, vol. 9, pp. 471 - 476, http://dx.doi.org/10.1007/s00792-005-0464-1
    Journal articles | 2005
    Siddiqui KS; Poljak A; Guilhaus M; Feller G; D Amico S; Gerday C; Cavicchioli R, 2005, 'Role of disulfide bridges in the activity and stability of a cold-active alpha-amylase', Journal of Bacteriology, vol. 187, pp. 6206 - 6212, http://dx.doi.org/10.1128/JB.187.17.6206-6212.2005
    Journal articles | 2005
    Afzal A; Ali S; Latif F; Rajoka M; Siddiqui KS, 2005, 'Innovative kinetic and thermodynamic analysis of a purified superactivexylanase from Scopulariopsis sp', Applied Biochemistry and Biotechnology, vol. 120, pp. 51 - 70, http://dx.doi.org/10.1385/ABAB:120:1:51
    Journal articles | 2004
    Siddiqui KS; Bokhari S; Afzal A; Singh S, 2004, 'A novel thermodynamic relationship based on Kramers Theory for study ingenzyme kinetics under high viscosity', IUBMB Life, vol. 56, pp. 403 - 407, http://dx.doi.org/10.1080/15216540400003052
    Journal articles | 2004
    Siddiqui KS; Poljak A; Cavicchioli R, 2004, 'Improved activity and stability of alkaline phosphatases from psychrophilic and mesophilic organisms by chemically modifying aliphatic or amino groups using tetracarboxy-benzophenone derivatives', Cellular and Molecular Biology, vol. 50, pp. 657 - 667
    Journal articles | 2002
    Cavicchioli R; Sowers KR; Siddiqui KS; Andrews D, 2002, 'Low-temperature extremophiles and their applications', Current Opinion in Biotechnology, vol. 13, pp. 253 - 261, http://dx.doi.org/10.1016/S0958-1669(02)00317-8
    Journal articles | 2002
    Siddiqui KS; Cavicchioli R; Thomas T, 2002, 'Thermodynamic activation properties of elongation factor 2 (EF-2) proteins from psychrotolerant and thermophilic Archaea', Extremophiles, vol. 6, pp. 143 - 150, http://dx.doi.org/10.1007/s007920100237
    Journal articles | 2002
    Bokhari SA; Afzal AJ; Rashid MH; Rajoka MI; Siddiqui KS, 2002, 'Coupling of surface carboxyls of carboxymethylcellulase with aniline via chemical modification: Extreme thermostabilization in aqueous and water-miscible organic mixtures', Biotechnology Progress, vol. 18, pp. 276 - 281, http://dx.doi.org/10.1021/bp010146h