Lan Guan, M.D. Ph.D. | Texas Tech University Health Sciences Center

Professor, Cell Physiology and Molecular Biophysics

Director, Center for Membrane Protein Research

lan guan

3601 4th Street, STOP 6551
Lubbock, Texas 79430
Office Phone: (806) 743-3102
Office Room: 5A148A

Research Interest:

Membrane proteins constitute ~30% of all eukaryotic proteins and play crucial roles in many aspects of cell function. The long-term goal of our research is to understand the mechanisms of solute transport. Currently, we are studying cation-coupled bacterial and human transporters by an integrated approach including X-ray crystallography, cryo-EM, ligand binding thermodynamics, genetic engineering, novel amphiphiles, and many other biochemical & biophysical analyses.

Current Support:

NIH Awards R01 & R21

Open position for PHD student


Guest Edited Collection - Scientific Reports

"Structure and mechanism of membrane transporters"

Submissions are still welcome on a rolling basis

2020 & Other Selected Publications:

  Guan, L. and Hariharan, P. (2020) Molecular recognition of sugar binding in a melibiose transporter MelBby X-ray crystallography. BioRxiv Preprint. doi:
  Das, M., Mahler, F., Hariharan, P., Wang, H., Du, Y., Mortensen, J., Patallo, E., Ghani, L., Glück, D., Lee, H.J., Byrne, B., Loland, C., Guan, L., Kobilka, B., Keller, S., and Chae, P.S. (2020) Diastereomeric cyclopentane-based maltosides (CPMs) as tools for membrane protein study. JACS
  Guan, L. (2020) Glucose/Sugar Transport in Bacteria. Encyclopedia of Biochemistry, 3rd edition, Elsevier Inc.
  Bae, H.E., Cecchetti, C., Du, Y., Katsube, S., Mortensen, J.S., Huang, W., Rehan, S., Lee, H.J.,  Loland, C.J., Guan, L., Kobilka, B.K., Byrne, B., and Chae, P.S. (2020) Pendant-bearing glucose-neopentyl glycol (P-GNG) amphiphiles for membrane protein manipulation: Importance of detergent pendant chain for protein stabilization. Acta Biomaterialia 112:250-261.
  Ehsan, M., Katsube, S., Cecchetti, C., Du, Y., Mortensen, J.S., Wang, H., Nygarrd, A., Ghani, L., Loland, C.J., Kobilka, B.K., Byrne, B., Guan, L., and Chae P.S. (2020) New malonate-derived tetraglucoside (MTG) detergents for mem-brane protein stability. ACS Chemical Biology 15(6):1697-1707. doi: 10.1021/acschembio.0c00316.
  Selected Publications in the Past Years
  H. Ronald Kaback and Lan Guan. (2019)  It takes two to tango: the dance of the permease. Accepted for publication by Journal of General Physiology  151(7):878-886. doi: 10.1085/jgp.201912377.
  Hariharan, P., Tikhonova, E., Medeiros-Silva, J., Jeucken, A., Bogdanov, M.V., Dowhan, W., Brouwers, J. F., Weingarth, M. and Guan, L. (2018) Structural and functional characterization of protein–lipid interactions of the Salmonella typhimurium melibiose transporter MelB. BMC Biology 16:85 doi: 10.1186/s12915-018-0553-0
  Guan, L. (2018) Na(+)/Melibiose Membrane Transport Protein, MelB. In: Roberts G., Watts A., European Biophysical Societies (eds) Encyclopedia of Biophysics. Springer. DOI: 10.1007/978-3-642-35943-9_10082-1
ncbi Hariharan, P. & Guan. L. (2017) Thermodynamic cooperativity of cosubstrate binding and cation selectivity of Salmonella typhimurium MelB. J Gen Physiol. (On the Cover and Highlighted by Research News, “A symporter’s secrets shown”). DOI: 10.1085/jgp.201711922. 149(11):1029-1039. DOI: 10.1085/jgp.201711788.
ncbi Hariharan, P., Balasubramaniam, D., Peterkofsky, A., Kaback, H.R., and Guan, L. (2015) Thermodynamic mechanism for inhibition of lactose permease by the phosphotransferase protein IIAGlc. Proc Natl Acad Sci USA. 112(8):2407-2412. DOI: 10.1073/pnas.1500891112.
ncbi Tikhonova, E.B., Ethayathulla, A.S., Su, Y., Hariharan, P., Xie, S., and Guan. L. (2015) A transcription blocker isolated from a designed repeat protein combinatorial library. Scientific Reports. 5:8070. DOI: 10.1038/srep08070.
ncbi Hariharan, P. & Guan, L. (2014) Insights into the inhibitory mechanisms of the regulatory protein IIAGlc on melibiose permease activity. J. Biol. Chem. 289(47):33012-33019. DOI: 10.1074/jbc.M114.609255.
ncbi Ethayathulla, A.S., Yousef, M.S., Amin, A., Leblanc, G., Kaback, H.R., and Guan, L. (2014) Structure-based mechanism for Na(+)/melibiose symport by MelB. Nature Communications. 5: 3009. DOI:10.1038/ncomms4009.
ncbi Chae, P.S., Rasmussen S.G.F., Rana, R., Gotfryd, K., Chandra, R., Goren, M.A., Kruse, A.C., Nurva, S., Loland, J.C., Pierre, Y., Drew, D., Popot, J.L., Picot, D., Fox, B.G., Guan, L., Gether, U., Byrne, B., Kobilka, B., and Gellman, S.H. (2010) Maltose–neopentyl glycol (MNG) amphiphiles for solubilization, stabilization, and crystallization of membrane proteins. Nature Methods.  7(12):1003-1008. DOI: 10.1038/nmeth.1526.
ncbi Guan, L., Mirza, O., Verner, G., Iwata, S, and Kaback, H.R. (2007) Structural determination of the wild-type lactose permease. Proc Natl Acad Sci U S A, 104 (39):15294-15298. DOI: 10.1073/pnas.0707688104.
ncbi Guan, L. & Kaback, H.R. (2007) Site-directed alkylation of cysteine to test solvent accessibility of membrane proteins. Nature Protocols. 2(28), 2012-2017. DOI: 10.1038/nprot.2007.275.
ncbi Guan, L. & Kaback, H.R. (2006) Lessons from lactose permease. Annual Review of Biophysics & Biomolecular Structure. (35):67-91.DOI: 10.1146/annurev.biophys.35.040405.102005.
ncbi Guan, L. & Kaback, H.R. (2004) Glucose/Sugar Transport in Bacteria. Encyclopedia of Biological Chemistry. 2; 204-207 (Elsevier Inc., updated in 2013). 

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Lan Guan, M.D. Ph.D.


Update on: 03/18/2021