[FeFe] hydrogenase genetic diversity provides insight into molecular adaptation in a saline microbial mat community

Abstract

Degenerate primers for the [FeFe] hydrogenase (hydA) were developed and used in PCRs to examine hydA in microbial mats that inhabit saltern evaporative ponds in Guerrero Negro (GN), Mexico. A diversity of deduced HydA was discovered that revealed unique variants, which may reflect adaptation to the environmental conditions present in GN.

FIG. 1.

(A) Phylogenetic tree based on deduced putative HydA amino acid sequences from GN and reference HydA sequences. Nodes with posterior probabilities of <50% were collapsed in this analysis (posterior probabilities of 100 are denoted by asterisks). Bar, one substitution per 10 sites. (B) Partial-length deduced amino acid sequences of environmental and reference deduced HydA sequences illustrating the phylogenetic coherence of novel substitutions and insertions in and upstream of L1 sequence motif. Cluster designations (C1 to C7) correspond to those presented in Table 1.