Single-stage hydrogen production from glucose was investigated using the marine photosynthetic bacterium Rhodovulum sulfidophilum TH-79, a Tn7 transposon mutant of strain P5. The mutation in strain TH-79 did not affect its cell growth in glucose medium compared with the parent strain. TH-79 displayed improved photoheterotrophic hydrogen production performance when the medium contained glucose or galactose as the sole carbon source. The mutant produced about 7.07 mol H-2/mol glucose, which is similar to the yields of more complicated integration systems. A one-stage photofermentation system using a seawater culture medium appears to be a promising alternative to the integration of dark- and photofermentation systems. Copyright (c) 2014, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.