Sulfur regulation of heparinase and sulfatases in Flavobacterium heparinum

Abstract

Sulfur regulation of heparinase synthesis and sulfatase synthesis was studied in Flavobacterium heparinum. Heparinase synthesis was strongly repressed by sulfate and L-cysteine, while the activity of this enzyme showed little or no inhibition by these compounds. Heparinase was synthesized in the absence of heparin when L-methionine was used as the sole sulfur source. The sulfatases produced by F. heparinum, which include the sulfatases involved in heparin catabolism, were also studied. At least some of the sulfatase activity was regulated by sulfur compounds in a manner similar to heparinase regulation. L-Cysteic acid and taurine were not suitable sulfur sources to support the growth of F. heparinum.

Riding the sulfur cycle – metabolism of sulfonates and sulfate esters in Gram-negative bacteria

“…In C. heparina, repression of both heparinase and sulfatase was seen when cysteine was added. As pointed out by Cerbelaud et al [16], the immediate drop in enzyme activity after addition of sulfate implies either the presence of speci¢c proteases, or a high endogenous turnover rate for the enzymes. Similar arguments have been invoked by Beil et al [184] to explain the repression of aromatic sulfonatases by sulfate or cysteine observed in P. putida S-313 (see below).…”

“…However, induction was also seen in the absence of heparin when the cells were grown in a sulfate-free medium with methionine as sole sulfur source [183]. During continuous growth in low-sulfate medium with methionine as sulfur source, synthesis of heparinase or heparin sulfatase could be temporarily turned o¡ by addition of limited amounts of sulfate [16]. The critical concentration causing repression was found to be between 10 and 70 WM, at which levels the sulfatase activity was not itself directly inhibited.…”

Riding the sulfur cycle – metabolism of sulfonates and sulfate esters in Gram-negative bacteria

“…In C. heparina , repression of both heparinase and sulfatase was seen when cysteine was added. As pointed out by Cerbelaud et al [16], the immediate drop in enzyme activity after addition of sulfate implies either the presence of specific proteases, or a high endogenous turnover rate for the enzymes. Similar arguments have been invoked by Beil et al [184] to explain the repression of aromatic sulfonatases by sulfate or cysteine observed in P. putida S‐313 (see below).…”

“…However, induction was also seen in the absence of heparin when the cells were grown in a sulfate‐free medium with methionine as sole sulfur source [183]. During continuous growth in low‐sulfate medium with methionine as sulfur source, synthesis of heparinase or heparin sulfatase could be temporarily turned off by addition of limited amounts of sulfate [16]. The critical concentration causing repression was found to be between 10 and 70 μM, at which levels the sulfatase activity was not itself directly inhibited.…”

“…Our understanding of the biochemical processes involved in organosulfur utilization by bacteria has leapt forward in recent years, with the characterization of several new sulfur‐regulated desulfurizing enzyme systems [11–16]. Additional information has become available through the sequencing of bacterial genomes, 21 of which have been completely sequenced at the time of writing.…”