Exhibit 31.1
CERTIFICATION OF PERIODIC REPORT UNDER SECTION 302 OF
THE SARBANES-OXLEY ACT OF 2002
I, Bertrand C. Liang, certify that:
| 1. | I have reviewed this Amendment No. 1 to the Quarterly Report on Form 10-Q/A of Pfenex Inc.; and |
| 2. | Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report. |
| Date: February 23, 2016 | /s/ Bertrand C. Liang | |||||
| Bertrand C. Liang | ||||||
| President and Chief Executive Officer | ||||||
| (Principal Executive Officer) |
